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 A225056 Smallest k such that q=2*k*prime(n)^4+b , r=2*k*q^4+c , s=2*k*r^4+d and q, r and s are all prime numbers with b, c and d = -1 or 1. 1

%I

%S 3199,339,1267,258,696,209,5514,4043,1773,390,4188,21735,4449,426,

%T 19410,14681,159,23475,1074,36876,1449,349,6525,4725,3141,354,2799,

%U 16164,369,8751,2385,9534,7973,6045,1644,17377,10574,21060,465,7734,24264,9630,43005

%N Smallest k such that q=2*k*prime(n)^4+b , r=2*k*q^4+c , s=2*k*r^4+d and q, r and s are all prime numbers with b, c and d = -1 or 1.

%H Pierre CAMI, <a href="/A225056/b225056.txt">Table of n, a(n) for n = 1..300</a>

%H Pierre CAMI, <a href="/A225056/a225056.txt">Program</a>

%e q=2*339*3^4-1=54917 prime, 3=prime(2),

%e r=2*339*54917^4-1=6166758091711727821637 prime,

%e s=2*339*6166758091711727821637^4-1 = 980522001959784653177131336948216283558445362942309523305624291540914216062705919811218757 prime,

%e so a(2)=339 with b=-1 c=-1 d=-1.