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A156027
Greater of twin primes pairs of the form k^1 + k^2 + k^3 + k^4 - 1.
1
5, 31, 22621, 837931, 3835261, 6377551, 16007041, 30397351, 147753211, 745720141, 987082981, 2439903211, 3276517921, 4178766091, 11468884081, 58714318141, 72695416561, 418374010741, 788251653691, 829180295191, 1029317536801, 3255573820801, 3343706188681
OFFSET
1,1
COMMENTS
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,...
LINKS
EXAMPLE
2 + 2^2 + 2^3 + 2^4 - 1 = 29 and 2 + 2^2 + 2^3 + 2^4 + 1 = 31.
MATHEMATICA
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
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Amiram Eldar, Dec 21 2019
STATUS
approved