OFFSET

1,2

PROG

(PARI) a(n) = { my(m=0, v = prime(n)*prime(n+1)); while (! isprime(v-m), m++; ); return (m); } \\ Michel Marcus, Apr 19 2013

CROSSREFS

KEYWORD

nonn

AUTHOR

Zak Seidov, May 10 2005

STATUS

approved