%I #6 Mar 29 2024 15:22:04
%S 2,2,2,2,9,9,9,224719,384427,16114470,259959472,13543584514,
%T 100318016379,100318016379
%N a(n) is the least integer m such that p#*m - 1 is prime for all primes p <= prime(n).
%H Martin Raab, <a href="https://arxiv.org/abs/2403.17949">A prime number "Game of Life": can floor(y*p#) be prime for all p>=2?</a>, arXiv:2403.17949 [math.GM], 2024.
%o (PARI) isok(m, n) = for(i=1, n, my(P = vecprod(primes(i))); if (! isprime(P*m-1), return(0));); return(1);
%o a(n) = my(m=1); while (!isok(m, n), m++); m;
%Y Cf. A002110.
%K nonn,more
%O 1,1
%A _Michel Marcus_, Mar 29 2024
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