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Greater of twin primes pairs of the form k^1 + k^2 + k^3 + k^4 - 1.
1

%I #12 Sep 08 2022 08:45:41

%S 5,31,22621,837931,3835261,6377551,16007041,30397351,147753211,

%T 745720141,987082981,2439903211,3276517921,4178766091,11468884081,

%U 58714318141,72695416561,418374010741,788251653691,829180295191,1029317536801,3255573820801,3343706188681

%N Greater of twin primes pairs of the form k^1 + k^2 + k^3 + k^4 - 1.

%C The corresponding values of k: 1, 2, 12, 30, 44, 50, 63, 74, 110, 165, 177, 222, 239, 254, 327, 492, 519, 804, 942, 954,...

%H Amiram Eldar, <a href="/A156027/b156027.txt">Table of n, a(n) for n = 1..10000</a>

%e 2 + 2^2 + 2^3 + 2^4 - 1 = 29 and 2 + 2^2 + 2^3 + 2^4 + 1 = 31.

%t lst={};Do[p=(n^1+n^2+n^3+n^4);If[PrimeQ[p1=p-1]&&PrimeQ[p2=p+1],AppendTo[lst,p2]],{n,8!}];lst

%o (Magma) [p+2:k in [1..1500] | IsPrime(p) and IsPrime(p+2) where p is k^1+k^2+k^3+k^4-1]; // _Marius A. Burtea_, Dec 21 2019

%Y Cf. A125964, A156018, A156021, A156026.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Feb 01 2009

%E More terms from _Amiram Eldar_, Dec 21 2019