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A343418 Primes that occur in A343416.

%I A343418 #7 Apr 18 2021 22:33:43
%S A343418 11,29,41,61,73,97,131,137,139,149,151,157,167,179,191,211,227,229,
%T A343418 233,241,251,283,293,307,313,331,347,373,383,389,397,401,449,463,521,
%U A343418 577,607,631,641,647,653,661,673,677,701,709,719,727,757,769,811,821,823,829,857,859,877,887,907,919,929
%N A343418 Primes that occur in A343416.
%C A343418 Terms are distinct and in numerical order, not the order they occur in A343416.
%C A343418 If p, 6*p-1 and 19*p+4 are prime, then 19*p+4 = A343416(6*p-1) is a term.  Dickson's conjecture implies that there are infinitely many such terms.
%H A343418 Robert Israel, <a href="/A343418/b343418.txt">Table of n, a(n) for n = 1..4000</a>
%e A343418 a(3) = 41 is a term because 41 = A343416(8) = A343416(10) and is prime.
%p A343418 spf:= proc(n) local t; add(t[1]*t[2],t=ifactors(n)[2]) end proc:
%p A343418 f:= proc(n) local a,b;
%p A343418   a:= spf(n);
%p A343418   b:= numtheory:-sigma(n);
%p A343418   a+b+spf(b)+numtheory:-sigma(a)
%p A343418 end proc:
%p A343418 S:= select(t -> t < 1000 and isprime(t), map(f, {$1..1000})):
%p A343418 sort(convert(S,list));
%Y A343418 Cf. A343416.
%K A343418 nonn
%O A343418 1,1
%A A343418 _J. M. Bergot_ and _Robert Israel_, Apr 14 2021