id:A089954 - OEIS Search Results

Search: id:A089954

Displaying 1-1 of 1 results found.

page 1

n+1 and sigma(n)+1 are both perfect squares.

+0
1

8, 15, 35, 120, 143, 323, 728, 899, 1520, 1763, 3599, 5183, 10403, 11663, 19043, 22499, 32399, 36863, 39203, 51983, 57599, 72899, 76728, 79523, 97343 (list; graph; listen)

	OFFSET	`1,1`
	MATHEMATICA	`Select[Range[10^5], IntegerQ[Sqrt[ # + 1]] && IntegerQ[Sqrt[DivisorSigma[1, # ] + 1]] &]`
	CROSSREFS	`Sequence in context: A132298 A123526 A083686 this_sequence A134020 A132810 A137658` `Adjacent sequences: A089951 A089952 A089953 this_sequence A089955 A089956 A089957`
	KEYWORD	`nonn`
	AUTHOR	`Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jan 17 2004`

page 1

Search completed in 0.002 seconds

Last modified July 23 17:35 EDT 2008. Contains 142285 sequences.

AT&T Labs Research