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%I #18 Apr 22 2019 15:23:48
%S 63,513,2107,12625,26533,39609,355023,3190833,4457713,19854847,
%T 38463283,242138449,370634743,516465451,574336561,701607583,
%U 1380336193,2324581983,4882890625,6174434113,12859758577,14793096853,20578440583,43522669657,85504120021
%N Odd terms in A305236.
%C These are numbers of the form p^e*((p-1)*p^(e-1) + 1) where p is an odd prime and (p-1)*p^(e-1) + 1 is prime.
%C {A002322(a(n))} = {6, 18, 42, 100, 156, 162, ...} is a permutation of A114874 without the terms that are powers of 2 (but they don't have the same order: 6563187324027001 and 6575415997816513 are both terms but A002322(6563187324027001) = 81009000 while A002322(6575415997816513) = 80995248).
%C A305236 = {a(n)} U {2*a(n)} U {8, 12}.
%H Jianing Song, <a href="/A307527/b307527.txt">Table of n, a(n) for n = 1..156</a> (all terms below 10^16)
%e See A305236 for examples.
%o (PARI) the_first_entries(nn) = my(u=[]); for(n=2, sqrt(nn), my(v=factor(n), d=#v[, 1], p=v[d, 1], e=v[d, 2]); if(isprime(n+1) && p!=2 && n==(p-1)*p^e, u=concat(u, [(n+1)*p^(e+1)]))); u=vecsort(select(i->(i<nn), u)); u
%Y Cf. A305236, A114874, A002322.
%K nonn
%O 1,1
%A _Jianing Song_, Apr 12 2019
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