A224494 Smallest k such that k*2*p(n)^2+1=q is prime and k*2*q^2+1 is also prime.

5, 2, 29, 41, 9, 2, 71, 30, 32, 6, 35, 11, 6, 50, 2, 20, 9, 120, 56, 21, 9, 75, 90, 51, 51, 29, 107, 9, 74, 155, 116, 11, 29, 86, 116, 35, 200, 12, 11, 39, 9, 105, 51, 422, 36, 65, 6, 32, 27, 44, 9, 41, 14, 116, 266, 41, 29, 5, 50, 95, 27, 71, 69, 330, 21, 194

Offset

1,1

Links

Pierre CAMI, Table of n, a(n) for n = 1..10000

Mathematica

a[n_] := For[k = 1, True, k++, p = Prime[n]; If[PrimeQ[q = k*2*p^2 + 1] && PrimeQ[k*2*q^2 + 1], Return[k]]]; Table[ a[n] , {n, 1, 66}] (* Jean-François Alcover, Apr 12 2013 *)

Crossrefs

Cf. A224489, A224490, A224491, A224492, A224493, A224495, A224496.

Sequence in context: A297812 A360546 A347379 * A095998 A328555 A208927

Adjacent sequences: A224491 A224492 A224493 * A224495 A224496 A224497

Keyword

nonn

Author

Pierre CAMI, Apr 08 2013

Status

approved