cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A217550 Numbers n such that s! + n^2 and (s + 2)! + n^2 are squares for some s, ordered by s.

Original entry on oeis.org

1, 179, 204, 108, 996, 2934, 81720, 2152080, 851040, 271106640, 7935621120, 1143137318400, 52250931532800
Offset: 1

Views

Author

Robin Garcia, Oct 06 2012

Keywords

Comments

The corresponding numbers s are: 5, 6, 7, 8, 9, 11, 12, 14, 16, 17, 19, 25, 27.

Examples

			5! + 1 = 11^2 and 7! + 1 = 71^2.
6! + 179^2 = 181^2 and 8! + 179^2 = 269^2.
7! + 204^2 = 216^2 and 9! + 204^2 = 636^2.
8! + 108^2 = 228^2 and 10! + 108^2 = 1908^2.
		

Crossrefs

Programs

  • PARI
    for(n=4,32,a=n!;b=((n+2)*(n+1)-1)*a;c=divisors(b);for(i=2,#c-1,s=c[i];r=b\s;if(r
    				

A217551 Smallest numbers n, for a given s, such that s! + n^2 and (s+3)! + n^2 are squares.

Original entry on oeis.org

1, 828, 508, 239499435, 4693095288000, 561589459200, 148245349824000
Offset: 1

Views

Author

Robin Garcia, Oct 06 2012

Keywords

Comments

The corresponding values of s are: 4, 8, 9, 15, 21, 24, 27.

Examples

			4! + 1 = 5^2 and 7! + 1 = 71^2.
8! + 828^2 = 852^2 and 11! + 828^2 = 6372^2.
		

Crossrefs

Programs

  • PARI
    for(n=4,30,a=n!;b=((n+3)*(n+2)*(n+1)-1)*a;c=divisors(b);for(i=2,#c-1,s=c[i];r=b\s;if(r
    				
Showing 1-2 of 2 results.