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%I #12 Apr 12 2018 02:40:36
%S 2,7,71,109,1321,1453,1621,1951,2719,3373,3853,4639,5791,6427,6733,
%T 9619,10837,11699,13933,15391,16927,18517,20173,23743,25633,28927,
%U 29599,33151,40813,43291,44959,47533,55711,56671,58579,70783,80671,84127,88813
%N Primes of the form n^2+number of divisors of n^2.
%H Robert Israel, <a href="/A188665/b188665.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A188539(n)^2 + A000005(A188539(n)^2).
%e a(5)=1321 because 36^2+A000005(36^2)=1321.
%p select(isprime, map(n -> n^2 + numtheory:-tau(n^2), [1, seq(i, i=2..1000, 2)])); # _Robert Israel_, Apr 11 2018
%t Select[Table[n^2+DivisorSigma[0,n^2],{n,300}],PrimeQ] (* _Harvey P. Dale_, Oct 20 2016 *)
%Y Cf. A000005, A188539.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Apr 07 2011
%E Edited by _Robert Israel_, Apr 11 2018