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%I #7 Apr 27 2017 10:45:17
%S 2,7,17,107,227,277,457,857,1627,3517,4517,5407,9767,11057,13877,
%T 15017,16607,20477,23767,26267,27827,35107,37517,41927,42577,50767,
%U 53657,58907,62017,68477,79657,83267,86027,93607,98507,110777,113957,128257,137477,145807
%N Primes equal to a centered pentagonal number plus 1.
%H Colin Barker, <a href="/A285810/b285810.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) cpg(m, n) = m*n*(n-1)/2+1 \\ n-th centered m-gonal number
%o maxk=600; L=List(); for(k=1, maxk, if(isprime(p=cpg(5, k) + 1), listput(L, p))); Vec(L)
%Y Cf. A000040, A005891, A285809, A285811, A285812.
%K nonn
%O 1,1
%A _Colin Barker_, Apr 27 2017
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