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%I #13 Jun 07 2021 04:46:13
%S 2,5,6,8,18,20,98,1863
%N Numbers k such that A136368(k) is prime.
%t f=0; Do[ p=Prime[n]; f=f + (-1)^(n+1)*1/p^2; g=Numerator[f] ;If[ PrimeQ[g], Print[ {n, g} ] ], {n, 1, 100} ]
%Y Cf. A024530 (numerator of Sum_{k=1..n} (-1)^k / prime(k)).
%Y Cf. A136368 (numerator of Sum_{k=1..n} (-1)^(k+1)/prime(k)^2).
%Y Cf. A136365, A136366, A136367, A136370, A136371.
%K nonn,more
%O 1,1
%A _Alexander Adamchuk_, Dec 27 2007
%E a(8) from _Robert Price_, Aug 28 2019
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