%I
%S 1,9,12,15,16,19,22,23,24,25,30,31,32,37,38,39,40,47,48,51,54,55,56,
%T 59,62,63,66,67,68,71,72,73,74,75,76,77,78,79,80,85,86,87,88,91,92,93,
%U 94,95,96,97,100,101,102,103,106,107,108,111,112,115,118,119,122,123,124
%N The positions of single (or isolated or nontwin) primes in A000040.
%F A000040(a(n))=A007510(k).
%p A176656 := proc(n) numtheory[pi](A007510(n)) ; end proc: seq(A176656(n),n=1..120) ; # _R. J. Mathar_, Apr 26 2010
%K nonn
%O 1,2
%A _JuriStepan Gerasimov_, Apr 23 2010
%E Corrected (32 inserted, one of the 94 removed, 103 inserted, 121 replaced by 122) by _R. J. Mathar_, Apr 26 2010
