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A224494 Smallest k such that k*2*p(n)^2+1=q is prime and k*2*q^2+1 is also prime. 4
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 (list; graph; refs; listen; history; text; internal format)
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: A117734 A007572 A297812 * A095998 A328555 A208927

Adjacent sequences:  A224491 A224492 A224493 * A224495 A224496 A224497

KEYWORD

nonn

AUTHOR

Pierre CAMI, Apr 08 2013

STATUS

approved

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Last modified April 5 00:43 EDT 2020. Contains 333238 sequences. (Running on oeis4.)