A135716 - OEIS

%I #2 Mar 30 2012 17:36:44

%S 119,144,210,245,260,285,317,352

%N Numbers n such that all numbers of the form p(n)#/p(k) +- 1, where 1 <= k <= n, are composite.

%C p(k) is k-th prime; p(n)# is n-th primorial, A002110(n). No more terms <= 500.

%F Numbers n such that A135714(n)+A135715(n)=0.

%e 119 is a term as p(119)#/p(k)+1 is composite for all 1 <= k <= 119 and p(119)#/p(k)-1 is likewise composite for the same k values; there are 238 such composite numbers.

%o (PARI)

%Y Cf. A135714, A135715, A002110.

%K nonn

%O 1,1

%A _Rick L. Shepherd_, Nov 30 2007