

A130796


Primes p such that nextprime(p)p is not power of 2.


1



23, 31, 47, 53, 61, 73, 83, 113, 131, 139, 151, 157, 167, 173, 181, 199, 211, 233, 241, 251, 257, 263, 271, 283, 293, 317, 331, 337, 353, 367, 373, 383, 409, 421, 433, 443, 467, 503, 509, 523, 541, 547, 557, 563, 571, 577, 587, 593, 601, 607, 619, 631, 647
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Indices of primes are 9,11,15,16,18,21,23,30,32,34,36,37,39,40,42,46,47,51, 53,54,55,56,58,61,62,66,... (subsequence of A113339).


LINKS

Table of n, a(n) for n=1..53.


MATHEMATICA

<<NumberTheory`NumberTheoryFunctions`; c=0; p=2; Do[p1=NextPrime[p]; If[ !IntegerQ[Log[2, p1p]], c++; a[c]=p]; p=p1, {200}]; Table[a[i], {i, c}]
Select[Prime[Range[200]], !IntegerQ[Log[2, NextPrime[#]#]]&] (* Harvey P. Dale, Apr 20 2011 *)


CROSSREFS

Cf. A001223 Differences between consecutive primes, A082509 Differences between consecutive primes that are not powers of 2, A082508 Differences between consecutive primes that are powers of 2, A113339 Integers n such that prime(n+1)prime(n) is nonprime, squarefree.
Sequence in context: A276435 A083370 A124582 * A258578 A031924 A257528
Adjacent sequences: A130793 A130794 A130795 * A130797 A130798 A130799


KEYWORD

nonn


AUTHOR

Zak Seidov, Aug 20 2007


STATUS

approved



