Number Recreations

Shyam Sunder Gupta
Executive Director Track(P),
141, Rail Bhawan, Ministry of Railways,
New Delhi, India-110001
Telephone: (011) 23382619(O), 23368426(R)

What is New? (Update 25th December, 2013)

The page on Curious Properties of 153 updated.

CYF NO. 38 Comments by Bernard Fischel given.

Prime curios 13, 4369, 10301, 15709, 75353, 91019, 123191, 303593, 442619, 1120211, 336737123, 904719030, 1123564987, 13201010231, 16831813861, 1123529253211, 3842148274728412483, 3868168229228618683, 164471141292141174461 and 14422...32163 (24-digits) added.

Do You Know?

There are 153 days in any five consecutive months not containing February.

Can You Find?

CYF NO. 44
The smallest odd abundant number with less than five prime factors (not necessarily distinct).

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Note: The above topics including many more will be added in due course.


My Contributions in Prime Curios

Prime Curios! - site maintained by G. L. Honaker Jr. and Chris Caldwell

My Favorite Links

  • Magic Squares,Magic Stars and Other Interesting number patterns by Harvey Heinz
  • Mudd Math Fun Facts pages
  • On-Line Encyclopedia of Integer Sequences OEIS
  • Math Puzzles
    An interesting site with lot of math recreations by Ed Pegg Jr.
  • World of Trotter Math
    Fascinating work on Number and other math recreations by dedicated mathematics teacher Terry Trotter.

My Favorite Books

Recommended list of books for those interested in Recreational and Computational Number theory
In Association with

The Rail
(January, 2003)

(March, 2003)
The Busy Educator Award
(October, 2003)

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This page was last updated on 25th December, 2013.


Copyright 2001-2014 Shyam Sunder Gupta. All rights reserved.