A097528 Least k such that k*P(n)#-P(n+4) and k*P(n)#+P(n+4) are both primes with P(i)=i-th prime and P(i)#=i-th primorial.

9, 3, 1, 1, 1, 9, 3, 1, 3, 3, 2, 21, 25, 17, 59, 47, 38, 23, 15, 41, 11, 53, 132, 5, 291, 52, 210, 64, 74, 14, 263, 692, 192, 641, 60, 65, 317, 137, 173, 264, 767, 477, 40, 213, 299, 676, 374, 340, 55, 1695, 656, 1066, 2235, 154, 356, 193, 123, 226, 906, 619, 69, 495

Offset

1,1

Links

Table of n, a(n) for n=1..62.

Mathematica

Primorial[n_] := Product[ Prime[i], {i, n}]; f[n_] := Block[{k = 1, p = Primorial[n], q = Prime[n + 4]}, While[k*p - q < 2 || !PrimeQ[k*p - q] || !PrimeQ[k*p + q], k++ ]; k]; Table[ f[n], {n, 62}] (* Robert G. Wilson v, Aug 31 2004 *)

Crossrefs

Sequence in context: A160579 A134897 A010159 * A065416 A093312 A154629

Adjacent sequences: A097525 A097526 A097527 * A097529 A097530 A097531

Keyword

easy,nonn

Author

Pierre CAMI, Aug 27 2004

Extensions

More terms from Robert G. Wilson v, Aug 31 2004

Status

approved