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

%I #10 Jan 30 2020 06:40:18

%S 3,29,22619,837929,3835259,6377549,16007039,30397349,147753209,

%T 745720139,987082979,2439903209,3276517919,4178766089,11468884079,

%U 58714318139,72695416559,418374010739,788251653689,829180295189

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

%C The corresponding values of k are 1, 2, 12, 30, 44, ... (A156021).

%H Amiram Eldar, <a href="/A156026/b156026.txt">Table of n, a(n) for n = 1..10000</a>

%e 29 is a term since 2 + 2^2 + 2^3 + 2^4 - 1 = 29 and 2 + 2^2 + 2^3 + 2^4 + 1 = 31 are twin primes.

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

%t Select[Table[n+n^2+n^3+n^4-1,{n,1000}],AllTrue[{#,#+2},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Dec 17 2019 *)

%Y Cf. A001359, A125964, A156018, A156021.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Feb 01 2009