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A224495 Smallest k such that k*2*p(n)^2+1=q is prime 2*k*q^2+1=r 2*k*r^2+1=s, r and s are also prime. 4

%I

%S 9,126,29,237,420,2,186,30,2349,896,1266,147,741,140,3021,924,19571,

%T 896,791,11495,32,7016,3522,5336,932,5480,107,1439,1770,209,4239,1716,

%U 477,1196,1446,900,9176,1920,2375,39,2351,590,2724,422,3171,179,1751,426,65

%N Smallest k such that k*2*p(n)^2+1=q is prime 2*k*q^2+1=r 2*k*r^2+1=s, r and s are also prime.

%H Pierre CAMI, <a href="/A224495/b224495.txt">Table of n, a(n) for n = 1..5600</a>

%t a[n_] := For[k = 1, True, k++, p = Prime[n]; If[PrimeQ[q = k*2*p^2 + 1] && PrimeQ[r = k*2*q^2 + 1] && PrimeQ[k*2*r^2 + 1], Return[k]]]; Table[ a[n] , {n, 1, 49}] (* _Jean-Fran├žois Alcover_, Apr 12 2013 *)

%Y Cf. A224489, A224490, A224492, A224492, A224493, A224494, A224496.

%K nonn

%O 1,1

%A _Pierre CAMI_, Apr 08 2013

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Last modified March 28 15:06 EDT 2020. Contains 333089 sequences. (Running on oeis4.)