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%I #15 Nov 06 2014 00:45:10
%S 2,3,5,7,11,13,17,29,37,43,47,59,67,71,79,89,97,107,109,127,137,139,
%T 167,181,191,197,199,211,223,227,229,251,263,283,311,331,337,347,353,
%U 389,409,439,443,449,457,461,463,467,503,521,557,587,599,601,617,619,631,641,677,683,719
%N Primes p such that sigma(p-k) = sigma(p+k) has no solution, where sigma is A000203.
%C Primes that are not in A070299. - _Franklin T. Adams-Watters_, Nov 02 2014
%H Charles R Greathouse IV, <a href="/A249644/b249644.txt">Table of n, a(n) for n = 1..373</a>
%e 2 is in this sequence because sigma(2-1) < sigma(2+1) and 2 is prime.
%e 23 is not in the sequence because sigma(23-3) = sigma(23+3) = 42.
%o (PARI) forprime(p=1,10^3,c=0;for(k=1,p-1,if(sigma(p+k)==sigma(p-k),c++;break));if(!c,print1(p,", "))) \\ _Derek Orr_, Nov 03 2014
%o (PARI) is(n)=forcomposite(c=15, n-1, if(sigma(c)==sigma(2*n-c), return(0))); isprime(n) \\ _Charles R Greathouse IV_, Nov 03 2014
%Y Cf. A000203, A070299.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Nov 02 2014
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