OKUMURA Hiroshi

J-GLOBAL         Last updated: Oct 17, 2019 at 08:45
 
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Name
OKUMURA Hiroshi
E-mail
hokmryandex.com

Published Papers

 
The arbelos in Wasan geometry: Ootoba's problem and Archimedean circles
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 91-97   Oct 2019   [Refereed]
The arbelos in Wasan geometry: Chiba's problem
OKUMURA Hiroshi
Global Journal of Advanced Research on Classical and Modern Geometries   8(2) 98-104   Oct 2019   [Refereed]
A characterization of the golden arbelos involving an Archimedean circle
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 67-71   Aug 2019   [Refereed]
A note on the arbelos in Wasan geometry: Satoh's problem and a circle pattern
OKUMURA Hiroshi
Mathematics and Informatics   62(3) 301-304   Jul 2019   [Refereed]
Arbeloi determined by a chord and solutions to Problems 2017-3-8 and 2019-3-4
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 41-50   Jun 2019   [Refereed]
Division by Zero Calculus and Pompe's Theorem
Tsutomu Matsuura, Hiroshi Okumura, Saburou Saitoh
Sangaku Journal of Mathematics   3 36-40   May 2019   [Refereed]
The arbelos in Wasan geometry, Tamura's problem
OKUMURA Hiroshi
Global Journal of Advanced Research on Classical and Modern Geometries   8(1) 33-36   Apr 2019   [Refereed]
The arbelos in Wasan geometry, problems of Izumiya and Nait\=o
OKUMURA Hiroshi
Journal of Classical Geometry   4 1-5   Mar 2019   [Refereed]
A note on the arbelos in Wasan geometry, Matsuda's problem
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 19-23   Feb 2019   [Refereed]
A note on the arbelos in Wasan geometry, Satoh's problem
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 15-16   Feb 2019   [Refereed]
A Remark on Archimedean Incircles of an Isosceles Triangle
OKUMURA Hiroshi
Forum Geometricorum   19 59-61   Feb 2019   [Refereed]
A note on the arbelos in Wasan geometry, a problem in Sampo Tenzan Tebikigusa Furoku
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 12-14   Feb 2019   [Refereed]
An analogue to Pappus chain theorem with division by zero
OKUMURA Hiroshi
Forum Geometricorum   18 409-412   Dec 2018   [Refereed]
Wasan Geometry and Division by Zero Calculus
Hiroshi Okumura, Saburou Saitoh
Sangaku Journal of Mathematics   2 57-73   Nov 2018   [Refereed]
Solution to Problem 2018-3-2
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 54-56   Oct 2018   [Refereed]
A Note on the Tangential Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   3 140-142   Sep 2018   [Refereed]
A new proof of the Gras theorem
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Global Journal of Advanced Research on Classical and Modern Geometries   7(2) 50-52   Sep 2018   [Refereed]
Applications of the division by zero calculus to Wasan geometry
Hiroshi Okumura, Saburou Saitoh
Global Journal of Advanced Research on Classical and Modern Geometries   7(2) 44-49   Sep 2018   [Refereed]
Theorems about Triangles Similar with the Feuerbach Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Arhimede Mathematical Journal   5(1) 2-10   Jul 2018   [Refereed]
Solution to 2017-1 Problem 4 with division by zero
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 27-30   Jul 2018   [Refereed]
Solution to the problem proposed in “Solution to 2017-3 Problem 5”
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 24-26   Jun 2018   [Refereed]
The Paskalev-Tchobanov Distance Formula and Some of its Applications
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   3 71-73   Jun 2018   [Refereed]
A New Proof of the Feuerbach theorem
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   3 69-70   Jun 2018   [Refereed]
Solution to 2017-3 Problem 5
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 17-21   Jun 2018   [Refereed]
Harmonic Mean and Division by Zero
Hiroshi Okumura, Saburou Saitoh
Forum Geometricorum   18 155-159   Jun 2018   [Refereed]
Is It Really Impossible To Divide By Zero?
OKUMURA Hiroshi
Biostatistics and Biometrics   7(1) 1-2   May 2018   [Refereed][Invited]
A note on Pappus chain and a collinear theorem
Abdilkadir Altintas, Hiroshi Okumura
Sangaku Journal of Mathematics   2 11-12   May 2018   [Refereed]
A note on an isosceles triangle containing a square and three congruent circles
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 8-10   May 2018   [Refereed]
Computer Discovered Mathematics: An Alternaitve Construction of Malfatti Squares
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Mathematics and Informatics   61(2) 171-174   Apr 2018   [Refereed]
Computer Discovered Mathematics: A note on the Grinberg homothety
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Global Journal of Advanced Research on Classical and Modern Geometries   7(1) 11-14   Apr 2018   [Refereed]
Wasan geometry with the division by 0
OKUMURA Hiroshi
International Journal of Geometry   8(1) 17-20   Apr 2018   [Refereed]
Triangles Homothetic with the Extouch Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   3 37-43   Mar 2018   [Refereed]
Intangents triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   3 44-48   Mar 2018   [Refereed]
Triangles Homothetic with the Intouch Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Mathematical Reflections   4(2) 1-6   Mar 2018   [Refereed]
Computer Discovered Mathematics: Constructions of Malfatti squares
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Mathematics and Informatics   61(1) 10-18   Mar 2018   [Refereed]
A Note on the Feuerbach triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
The Mathematical Gazette   102(553) 135-138   Mar 2018   [Refereed]
Distance from the incentre of the tangential triangle of an obtuse triangle to the Euler line
Sava Grozdev, Hiroshi Okumura, Deko Dekov
The Mathematical Gazette   102(553) 133-135   Mar 2018   [Refereed]
A note on a problem involving a square in a curvilinear triangle
OKUMURA Hiroshi
Sangaku Journal of Mathematics   2 3-5   Feb 2018   [Refereed]
Remarks for The Twin Circles of Archimedes in a Skewed Arbelos by Okumura and Watanabe
Hiroshi Okumura, Saburou Saitoh
Forum Geometricorum   18 97-100   Feb 2018   [Refereed]
Problems for Students about Triangles Similar with the Extouch Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Didactical Modeling   6 29-39   Feb 2018   [Refereed]
Haga's theorems in paper folding and related theorems in Wasan geometry Part 2
OKUMURA Hiroshi
arxiv.org   1-12   Feb 2018
A Remark on the Arbelos and the Regular Star Polygon
OKUMURA Hiroshi
Forum Geometricorum   18 43-44   Jan 2018   [Refereed]
Haga's theorems in paper folding and related theorems in Wasan geometry Part 1
OKUMURA Hiroshi
Sangaku Journal of Mathematics   1 42-56   Dec 2017   [Refereed]
Haga's theorems in paper folding and related theorems in Wasan geometry Part 1
OKUMURA Hiroshi
arxiv.org   1-14   Nov 2017
Wasan geometry with the division by 0
OKUMURA Hiroshi
arxiv.org   1-4   Nov 2017
The Descartes circles theorem and division by zero calculus
OKUMURA Hiroshi, Saitoh Saburou
arxiv.org   1-9   Nov 2017
A note on the problems involving congruent circles in Tenzan Kaitei
OKUMURA Hiroshi
Sangaku Journal of Mathematics   1 39-41   Nov 2017   [Refereed]
A SURVEY OF MATHEMATICS DISCOVERED BY COMPUTERS. PART 2.
Sava Grozdev, Hiroshi Okumura, Deko Dekov
Mathematics and Informatics   60(6) 543-550   Dec 2017   [Refereed]
Theorems on two congruent circles on a line
OKUMURA Hiroshi
Sangaku Journal of Mathematics   1 35-38   Oct 2017   [Refereed]
Configurations of congruent circles on a line
OKUMURA Hiroshi
Sangaku Journal of Mathematics   1 24-34   Oct 2017   [Refereed]
Computer Discovered Mathematics: Problems for Students about Excentral Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 185-200   Oct 2017   [Refereed]
Problems on the Brocard circle
Save Grozdev, Hiroshi Okumura, Deko Dekov
Mathematics and Informatics   60(4) 382-390   Aug 2017   [Refereed]
Computer Discovered Mathematics: Notable Circles
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 117-134   Jun 2017   [Refereed]
Leversha Triangles and Leversha Points
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 111-116   Jun 2017   [Refereed]
Computer Discovered Mathematics: Triangles Associated with Triangulation Triangles
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 106-110   Jun 2017   [Refereed]
Triangles Homothetic with Triangle ABC. Part 3
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 97-105   Jun 2017   [Refereed]
Triangles Homothetic with Triangle ABC. Part 2
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 90-96   May 2017   [Refereed]
Triangles Homothetic with Triangle ABC
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2 86-89   Apr 2017   [Refereed]
Poristic triangles of the arbelos
Antonio Gutierrez, Hiroshi Okumura, Hussein Tahir
International Journal of Geometry   6(1) 27-35   Apr 2017   [Refereed]
Computer Discovered Mathematics: Problems about Points on the Euler line
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 81-85   Mar 2017   [Refereed]
Computer Discovered Mathematics: Excenters-Incenter Reflections Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 72-80   Mar 2017   [Refereed]
Relations of 0 and infinity
Hiroshi Okumura, Saburou Saitoh, Tsutomu Matsuura
Journal of Technology and Social Science   1(1) 70-77   Mar 2017   [Refereed]
A three tangent congruent circle problem
Yasuo Kanai, Hiroshi Okumura
Sangaku Journal of Mathematics   1 16-20   Mar 2017   [Refereed]
Computer Discovered Mathematics: Half-Anticevian Triangle of the Incenter
Sava Grozdev, Hiroshi Okumura, Deko Dekov,
International Journal of Computer Discovered Mathematics   2(1) 55-71   Feb 2017   [Refereed]
Computer Discovered Mathematics: Triangles homothetic with the Orthic triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 46-54   Feb 2017   [Refereed]
Computer Discovered Mathematics: Incentral Triangle
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 35-45   Feb 2017   [Refereed]
A Note on the Leversha Point
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 30-34   Jan 2017   [Refereed]
Japanese mathematics
OKUMURA Hiroshi
Sangaku Journal of Mathematics   1 1-6   Jan 2017   [Refereed]
Division by Zero z/0 = 0 in Euclidean Spaces
Hiroshi Michiwaki, Hiroshi Okumura, Saburoh Saitoh
International Journal of Mathematics and Computation   28(1) 1-16   Jan 2017   [Refereed]
Computer Discovered Mathematics: Euler Anticevian Triangles
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   2(1) 1-29   Jan 2017   [Refereed]
A Characterization of the Golden Arbelos
OKUMURA Hiroshi
Mathematical Medley   42(2) 3-5   Dec 2016   [Refereed]
Computer Discovered Mathematics: Grebe Triangles
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   1(4) 14-23   Nov 2016   [Refereed]
Computer Discovered Mathematics: Haimov Triangle of the Incenter
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   1(3) 57-61   Oct 2016   [Refereed]
Computer Discovered Mathematics: Orthopoles
Sava Grozdev, Hiroshi Okumura, Deko Dekov
International Journal of Computer Discovered Mathematics   1(3) 50-56   Oct 2016   [Refereed]
An equilateral triangle in the arbelos
OKUMURA Hiroshi
International Journal of Geometry   5(2) 93-95   Oct 2016   [Refereed]

Misc

 
アルキメデスからの贈り物21回 和算の幾何学に現れたアルベロス,田村の問題
OKUMURA Hiroshi
Kagaku   89(9)    Sep 2019
Problems 2019-2
OKUMURA Hiroshi
Sangaku Journal of Mathematics   3 24-25   Feb 2019   [Refereed]
アルキメデスからの贈り物20回 アルベロスと星形正多角形
奥村 博
Kagaku   89(1) 74-75   Jan 2019
アルキメデスからの贈り物19回 黄金アルベロス
奥村 博
Kagaku   88(6) 629-629   Jun 2018
甘木市八幡神社の算額題について
奥村 博
Shotoh Sugaku   (83) 31-33   Apr 2018
Hiroshi Okumura
Sangaku Journal of Mathematics   1 11-12   Feb 2017   [Refereed]
We propose two problems arising from figures appeared in sangaku problems in Fukushima.
アルキメデスからの贈り物18回 アルベロスと正三角形
奥村 博
Kagaku   88(1) 52-52   Jan 2017
課題76-3の一般化
OKUMURA Hiroshi
初等数学(初等数学の会)   (80) 24-25   Jan 2017
アルキメデスからの贈り物17回 歪んだアルベロスのアルキメデスの円
奥村 博
Kagaku   86(10) 1070-1074   Oct 2016
A note on Problem 73-2
OKUMURA Hiroshi
Shotoh Sugaku   (78) 40-41   Mar 2016
Origamics involving circles
OKUMURA Hiroshi
37-42   Feb 2016
Problem 158
Save Grozdev, Hiroshi Okumura, Deko Dekov
MathProblems Journal   6(2) 560-560   2016
アルキメデスからの贈り物16回 アルベロスの内接正方形
奥村 博
Kagaku   85(11) 1068-1069   Nov 2015
アルキメデスからの贈り物15回 最近発見されたアルキメデスの円
奥村 博
Kagaku   85(5) 0462-0463   May 2015
アルキメデスからの贈り物14回 和算の公式から導かれる3つ子のアルキメデスの円
奥村 博
Kagaku   84(6) 624-628   Jun 2014
アルキメデスからの贈り物13回 アルベロスとサリノンの面積
奥村 博
Kagaku   83(11) 1307-1309   Nov 2013
アルキメデスからの贈り物12回 和算の公式から導かれるユビキタスなアルキメデスの円
奥村 博
Kagaku   82(12) 1349-1351   Dec 2012
アルキメデスからの贈り物11回 歪んだアルベロスから導かれるアルキメデスの円
奥村 博
Kagaku   82(12) 1347-1348   Dec 2012
アルキメデスからの贈り物10回 歪んだアルベロス再論
奥村 博
Kagaku   81(11) 1146-1148   Nov 2011
アルキメデスからの贈り物9回 非アルキメデス的な双子の円
奥村博,渡辺雅之
Kagaku   80(4) 404-405   2010
アルキメデスからの贈り物8回 合同な双子の円をもつ複数のアルベロス
奥村博,渡辺雅之
Kagaku   79(3) 261-263   Mar 2009
アルキメデスからの贈り物7回 内部の2円の接点を通るアルキメデスの円(その2)
奥村博,渡辺雅之
Kagaku   78(2) 145-146   Feb 2008
無理数による変奏曲
奥村 博
Kagaku   78(2) 141-142   2008
アルキメデスからの贈り物5回 内部の2円の接点を通るアルキメデスの円(その1)
奥村博,渡辺雅之
Kagaku   77(12) 1247-1248   Dec 2007
アルキメデスからの贈り物6回 Power のアルキメデスの円
奥村博,渡辺雅之
Kagaku   77(9) 992-993   Sep 2007
アルキメデスからの贈り物3回 Schoch のアルキメデスの円
奥村博,渡辺雅之
Kagaku   76(10) 1053-1055   Oct 2006
アルキメデスからの贈り物4回 歪んだアルベロス(その2)
奥村博,渡辺雅之
Kagaku   76(4) 406-409   Apr 2006
アルキメデスからの贈り物1回 歪んだアルベロス(その1)
奥村博,渡辺雅之
Kagaku   75(11) 1314-1318   Nov 2005
アルキメデスからの贈り物2回 21世紀によみがえるアルベロス
奥村博,渡辺雅之
Kagaku   75(6) 746-749   Jun 2005
算額図形とフラクタル
奥村 博
Manifold   #6 3-4   2003
Rendering Algorithm of a Motion Blur Image Using Adaptive Distributed Ray Tracing : A High Speed Image Signal Processing for Three Dimensional Computer Graphics
NIINO Takahiro, OKUMURA Hiroshi, Sodeyama Chuich
Bulletin of Maebashi Institute of TechnologyB   4 89-90   Mar 2001
算額図形と黄金比
奥村 博
Manifold   #02 3-5   2001
The Separation of Polyphonic Tone of Different Class of Two Musical Instruments
Minoru TODA, Hiroshi OKUMURA, Chuichi Sodeyama
3 97-102   Mar 2000
EnjoyできMath数学コンテスト
OKUMURA Hiroshi
初等数学   (37) 99-102   Aug 1999
Mathematical study of Wasan geometry
OKUMURA Hiroshi
Proceedings of Fourth international symposium on the history of mathematics using Chinese characters   129-139   1999
安中周辺の数学
OKUMURA Hiroshi
安中図書館報   (46) 1-3   1987

Books etc

 
Origami^3
OKUMURA Hiroshi
A K Peters   Jul 2002   
The Pattern Book: Fractals, Art, and Nature
OKUMURA Hiroshi (Part:Joint Work, A generalization of the regular tiling (4^4), A pattern bu Fujita configurations)
World Scientific   Jul 1995   

Conference Activities & Talks

 
Twin circles in a triangle and its application to an arbelos
Hiroshi Okumura and Masayuki Watanabe
International Conference "Synergetics and reflection in mathematics education", At Bachinovo, Bulgaria   10 Sep 2010   

Social Contribution

 
Mathematical Reviews, reviewer
[Report writing]
Zentralblatt MATH, reviewer
[Report writing]
International Journal of Computer Discovered Mathematics, editor in chief
[Chief Editor, Editor, Planner]
Sangaku Journal of Mathematics, editor-in-chief
[Chief Editor, Editor, Planner]