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%I #9 Nov 15 2021 04:42:16
%S 2,5,11,17,19,23,29,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,
%T 107,109,113,131,137,139,149,151,157,163,167,173,179,181,191,193,197,
%U 199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293
%N Primes p such that the equation sigma(x) = p has no solution.
%H Amiram Eldar, <a href="/A070957/b070957.txt">Table of n, a(n) for n = 1..10000</a>
%t r = Range[300]; Complement[Select[r, PrimeQ], DivisorSigma[1, r]] (* _Amiram Eldar_, Nov 15 2021 *)
%o (PARI) for(n=1,100,if(sum(j=1,n,if(sigma(j)-n,1-isprime(n),1))==0,print1(n,",")))
%Y The prime terms in A007369.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, May 16 2002
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