A139462 a(n) = m such that product n successive odd primes - 2*prime(n+m+1) is prime = such m that primorial(n+1)/2 - 2*prime(n+m+1) is prime.

1, 2, 1, 1, 3, 1, 2, 2, 3, 1, 6, 5, 5, 7, 1, 5, 8, 2, 10, 29, 3, 7, 10, 8, 33, 28, 11, 3, 19, 5, 12, 12, 11, 19, 52, 29, 17, 23, 29, 36, 3, 1, 7, 59, 16, 5, 4, 113, 1, 8, 16, 25, 4, 5, 52, 1, 82, 71, 14, 34, 20, 3, 1, 35, 20, 107, 14, 38, 41, 34, 14, 6, 20, 36, 36, 20, 62, 19, 8, 92, 140

Offset: 1

Author

Artur Jasinski, Apr 22 2008

Keywords

• nonn

Comments

For indices where 1 occurs, see A139463.

Crossrefs

Cf. A067026, A067027, A139439, A139440, A139441, A139442, A139443, A139444, A139445, A139446, A139447, A139448, A139449, A139450, A139451, A139452, A139453, A139454, A139455, A139456, A139457, A103514, A139460, A139461, A139462, A139463.

Programs

Mathematica

k = 1; a = {}; Do[k = k*Prime[n]; m = 1; While[ ! PrimeQ[k - 2*Prime[n + m]], m++ ]; Print[m]; AppendTo[a, m], {n, 2, 200}]; a (*Artur Jasinski*)