Number Recreations

Shyam Sunder Gupta
Former Principal Chief Engineer,
North Western Railway, Jaipur, India-302017

What is New? (Update 12 September, 2022)

The page on Fascinating Triangular Numbers updated.

CYF NO. 49 Comments by Daniel Suteu given.

CYF NO. 56 Solution by Alessandro Casini given.

CYF NO. 55 Contribution by Al Zimmermann and Maximilian given.

Do You Know?

    √764 = 27.64054992...
    √76394 = 276.3946453895...
    √7639321 = 2763.9321626986...
    √763932023 = 27639.3202340433...

Can You Find?

CYF NO. 57
A repunit number, which can be represented as difference of two squares in exactly three different ways.

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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.

My Favorite Books

Recommended list of books for those interested in Recreational and Computational Number theory
In Association with 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 12th September, 2022.

Copyright 2021-2022 Shyam Sunder Gupta. All rights reserved.