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%I #11 Aug 18 2024 03:58:48
%S 1,5,10,11,14,15,20,23,24,28,29,34,35,38,39,40,42,44,46,48,52,56,57,
%T 59,60,62,65,66,68,69,74,75,76,82,85,87,92,95,97,102,106,109,114,118,
%U 119,120,122,124,126,133,136,137,139,143,145,146,148,149,152,153,156
%N Numbers k such that sigma(k) plus the k-th prime is a prime.
%H Robert Israel, <a href="/A116033/b116033.txt">Table of n, a(n) for n = 1..10000</a>
%e sigma(145)+prime(145) = 1009 (prime).
%p select(k -> isprime(numtheory:-sigma(k) + ithprime(k)), [$1..1000]); # _Robert Israel_, Aug 18 2024
%t Select[Range[156],PrimeQ[DivisorSigma[1,#]+Prime[#]]&] (* _James C. McMahon_, Aug 18 2024 *)
%Y Cf. A116034.
%K nonn
%O 1,2
%A _Giovanni Resta_, Feb 13 2006