Showing posts with label Combinatorics. Show all posts
Showing posts with label Combinatorics. Show all posts

Thursday, March 24, 2011

Combinatorics of Khadaffi

 Given Libya's current political turmoil, and as a student studying Combinatorics (the study of counting), I must ask:  In how many different ways can you spell the name of Libya's ruthless leader?  Perhaps there is no formal construction for such a thing, but the Library of Congress and various press have used the following spellings for him*:
  1. Qaddafi, Muammar
  2. Al-Gathafi, Muammar
  3. Al-Qadhafi, Muammar
  4. Al Qathafi, Mu'ammar
  5. Al Qathafi, Muammar
  6. El Gaddafi, Moamar
  7. El Kadhafi, Moammar
  8. El Kazzafi, Moamer
  9. El Qathafi, Mu'Ammar
  10. Gadafi, Muammar
  11. Gaddafi, Moamar
  12. Gadhafi, Mo'ammar
  13. Gathafi, Muammar
  14. Ghadafi, Muammar
  15. Ghaddafi, Muammar
  16. Ghaddafy, Muammar
  17. Gheddafi, Muammar
  18. Gheddafi, Muhammar
  19. Kadaffi, Momar
  20. Kad'afi, Mu`amar al- 20
  21. Kaddafi, Muamar
  22. Kaddafi, Muammar
  23. Kadhafi, Moammar
  24. Kadhafi, Mouammar
  25. Kazzafi, Moammar
  26. Khadafy, Moammar
  27. Khaddafi, Muammar
  28. Moamar al-Gaddafi
  29. Moamar el Gaddafi
  30. Moamar El Kadhafi
  31. Moamar Gaddafi
  32. Moamer El Kazzafi
  33. Mo'ammar el-Gadhafi
  34. Moammar El Kadhafi
  35. Mo'ammar Gadhafi
  36. Moammar Kadhafi
  37. Moammar Khadafy
  38. Moammar Qudhafi
  39. Mu`amar al-Kad'afi
  40. Mu'amar al-Kadafi
  41. Muamar Al-Kaddafi
  42. Muamar Kaddafi
  43. Muamer Gadafi
  44. Muammar Al-Gathafi
  45. Muammar al-Khaddafi
  46. Mu'ammar al-Qadafi
  47. Mu'ammar al-Qaddafi
  48. Muammar al-Qadhafi
  49. Mu'ammar al-Qadhdhafi
  50. Mu`ammar al-Qadhdhāfī 50
  51. Mu'ammar Al Qathafi
  52. Muammar Al Qathafi
  53. Muammar Gadafi
  54. Muammar Gaddafi
  55. Muammar Ghadafi
  56. Muammar Ghaddafi
  57. Muammar Ghaddafy
  58. Muammar Gheddafi
  59. Muammar Kaddafi
  60. Muammar Khaddafi
  61. Mu'ammar Qadafi
  62. Muammar Qaddafi
  63. Muammar Qadhafi
  64. Mu'ammar Qadhdhafi
  65. Muammar Quathafi
  66. Mulazim Awwal Mu'ammar Muhammad Abu Minyar al-Qadhafi
  67. Qadafi, Mu'ammar
  68. Qadhafi, Muammar
  69. Qadhdhāfī, Mu`ammar
  70. Qathafi, Mu'Ammar el 70
  71. Quathafi, Muammar
  72. Qudhafi, Moammar
  73. Moamar AI Kadafi
  74. Maummar Gaddafi
  75. Moamar Gadhafi
  76. Moamer Gaddafi
  77. Moamer Kadhafi
  78. Moamma Gaddafi
  79. Moammar Gaddafi
  80. Moammar Gadhafi
  81. Moammar Ghadafi
  82. Moammar Khadaffy
  83. Moammar Khaddafi
  84. Moammar el Gadhafi
  85. Moammer Gaddafi
  86. Mouammer al Gaddafi
  87. Muamar Gaddafi
  88. Muammar Al Ghaddafi
  89. Muammar Al Qaddafi
  90. Muammar Al Qaddafi
  91. Muammar El Qaddafi
  92. Muammar Gadaffi
  93. Muammar Gadafy
  94. Muammar Gaddhafi
  95. Muammar Gadhafi
  96. Muammar Ghadaffi
  97. Muammar Qadthafi
  98. Muammar al Gaddafi
  99. Muammar el Gaddafy
  100. Muammar el Gaddafi
  101. Muammar el Qaddafi
  102. Muammer Gadaffi
  103. Muammer Gaddafi
  104. Mummar Gaddafi
  105. Omar Al Qathafi
  106. Omar Mouammer Al Gaddafi
  107. Omar Muammar Al Ghaddafi
  108. Omar Muammar Al Qaddafi
  109. Omar Muammar Al Qathafi
  110. Omar Muammar Gaddafi
  111. Omar Muammar Ghaddafi
  112. Omar al Ghaddafi
I suppose the issue here is that there is no generally accepted methodology to romanize Arabic names.  Further, his name contains several sounds that may not have an exact equivalence in English. 

Can you think of any other ways to spell his name?  How about R-U-T-H-L-E-S-S?!

*List from http://www.abcnews.com/

Thursday, January 27, 2011

Adding and Counting by Ken Ono

Last Friday, I attended an Emory Public Lecture titled "Adding and Counting" by Ken Ono.  During this well attended lecture, Professor Ono beautifully revealed the new theory he and his colleagues have discovered:  that partition functions behave like fractals and a closed formula to count the number of partitions for any number n.  The results confirm an observation made by Ramanujan in 1919.



The partition function p(n) counts the number of ways a number n can be partitioned.  For instance, over addition, n=4 may be partition in five distinct ways:  1+1+1+1=1+1+2=1+3=2+2=4.  Thus, p(4)=5.  For a better idea of what it means to "behave like fractals", watch the video above and notice the same structure appears repeatedly upon zooming in.  A formula for p(n) has intrigued mathematicians for centuries.

Professor Ono joined the faculty of the Mathematics Department at Emory University last semester and I have had the pleasure of taking a Number Theory course with him last semester.  For more information on this new theory, please see the Emory eScienceCommons and AMS press release.  Congrats to Professor Ono and his team on this remarkable advancement of Mathematics!

Thursday, January 20, 2011

Back to School

With 4-6 inches of snow and only 6 plows, icy Atlanta transformed to Hoth-lanta last week, resulting in a 5-day extended winter break for University students.  Although there was a delay in the start of the semester, there was no delay in discussing interesting topics in my Combinatorics course this week. 

A Steiner system with parameters l, m, n such that l<m<n is an n-element set S with an m-element subset of S (called blocks) such that any l-element subset of S is contained in exactly one block.  To simplify, let l=2 and m=3 to form a Steiner triple system S(2,3,n).  For what n does a Steiner triple system exist?
 
This question inspired Reverend Thomas Kirkman and he solved a special case of this problem in 1847.  His solution is widely known as the Kirkman Schoolgirl Problem.  So in the spirit of a fresh, new semester, here is the riddle for you:  15 girls walk to school each day in five groups of three.  How many days does it take for each pair of girls to walk together exactly once?  Note this is a Steiner triple system S(2,3,n) where n is the number of days.  Hint:  See picture.