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Numbers n such that A014285(n) is prime.
1

%I #5 May 25 2018 08:33:24

%S 1,3,32,63,67,75,88,99,104,115,116,120,135,144,159,167,179,188,192,

%T 195,199,204,227,239,244,260,280,283,304,323,335,348,351,379,380,384,

%U 396,412,424,436,443,503,508,523,579,632,648,651,695,723,724,736,743,752

%N Numbers n such that A014285(n) is prime.

%o (PARI) isok(n) = isprime(sum(i=1, n, i*prime(i))); \\ _Michel Marcus_, May 25 2018

%Y Cf. A014285 (Sum i*prime(i); i=1..n), A114256 (Prime numbers in A014285).

%K nonn

%O 1,2

%A _Zak Seidov_, Nov 18 2005