A156026 Lesser of twin primes of the form k^1 + k^2 + k^3 + k^4 - 1.

3, 29, 22619, 837929, 3835259, 6377549, 16007039, 30397349, 147753209, 745720139, 987082979, 2439903209, 3276517919, 4178766089, 11468884079, 58714318139, 72695416559, 418374010739, 788251653689, 829180295189

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, Feb 01 2009

Keywords

• nonn

Comments

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

Examples

			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.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A001359, A125964, A156018, A156021.

Programs

Mathematica

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
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 *)