id:A103665 - OEIS Search Results

Search: id:A103665

Displaying 1-1 of 1 results found.

page 1

Primes p such that the number of divisors of p-1 is greater than the number of divisors of p+1.

+0
4

13, 31, 37, 43, 61, 67, 73, 97, 101, 109, 113, 127, 151, 157, 163, 181, 193, 211, 229, 241, 257, 271, 277, 281, 283, 313, 331, 337, 353, 373, 379, 397, 401, 409, 421, 433, 457, 463, 487, 521, 523, 541, 547, 571, 577, 601, 613, 617, 631, 641, 661, 673, 677 (list; graph; listen)

	OFFSET	`1,1`
	COMMENT	`Mathematica coding by Wouter Meeussen (wouter.meeussen(AT)pandora.be) and Robert G. Wilson v (rgwv(AT)rgwv.com).`
	EXAMPLE	`a(1)=13 because d(12)=6 > d(14)=4.`
	MATHEMATICA	`Select[Prime[Range[2, 140]], Length[Divisors[ # - 1]] > Length[Divisors[ # + 1]] &]`
	CROSSREFS	`Cf. A008328 number of divisors of p-1, A008329 number of divisors of p+1, A103664, A103666, A103667.` `Sequence in context: A046414 A023694 A038465 this_sequence A040050 A040086 A023274` `Adjacent sequences: A103662 A103663 A103664 this_sequence A103666 A103667 A103668`
	KEYWORD	`nonn`
	AUTHOR	`Hugo Pfoertner (hugo(AT)pfoertner.org), Feb 19 2005`

page 1

Search completed in 0.002 seconds

Last modified July 26 13:41 EDT 2008. Contains 142293 sequences.

AT&T Labs Research