|
%I #9 Mar 14 2020 05:03:14
%S 1,1,1,1,1,1,1,5,3,1,2,5,13,2,8,3,4,5,16,2,3,3,16,23,4,8,6,10,38,18,
%T 20,11,1,14,7,21,52,2,13,4,5,12,6,1,38,12,36,1,8,3,43,1,4,32,4,19,12,
%U 45,45,41,118,14,40,1,26,43,2,4,13,15,128,6,1,20,29,9,14,9,36,6,104,9,14,26,9
%N a(n) = smallest number k such that n! + k-th prime after n is prime.
%C Because numbers of the form : (n! + prime) are divisible by all primes <= n that mean that first prime number can have form n! + k-th prime after n and no primes of the form n! + k for k > 1 and k < next prime after n
%H Amiram Eldar, <a href="/A151903/b151903.txt">Table of n, a(n) for n = 1..402</a>
%t a = {}; Do[k = 1; While[ ! PrimeQ[n! + NextPrime[n, k]], k++ ]; AppendTo[a, k], {n, 1, 200}]; a
%Y Cf. A002981, A151892, A151894, A151893, A139213, A139214.
%K nonn
%O 1,8
%A _Artur Jasinski_, Apr 12 2008
|
