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A121616 Nexus primes of order 5 or primes of form n^5 - (n-1)^5 = A022521[n-1]. 7
31, 211, 4651, 61051, 371281, 723901, 1803001, 2861461, 4329151, 4925281, 7086451, 7944301, 14835031, 19611901, 23382031, 44119351, 54664711, 86548801, 97792531, 162478501, 189882031, 267217051, 293109961, 306740281, 490099501 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Indices n such that Nexus number of order 5 (or A022521[n-1] = n^5 - (n-1)^5) is prime are listed in A121617[n] = {2,3,6,11,17,20,25,28,31,32,35,36,42,45,47,55,58,65,67,76,79,86,88,89,100,...}. Last digit is always 1 because 5 is Pythagorean prime A002144[1]. a(1) = 31 is Mersenne prime A000668[3].

LINKS

Zak Seidov, Table of n, a(n) for n = 1..2000.

MATHEMATICA

Select[Table[n^5 - (n-1)^5, {n, 1, 200}], PrimeQ]

CROSSREFS

Cf. A022521, A000040, A000043, A002144, A000668, A002407, A121617, A121618, A121619, A121620.

Sequence in context: A152730 A090027 A164784 * A062393 A183792 A183784

Adjacent sequences:  A121613 A121614 A121615 * A121617 A121618 A121619

KEYWORD

nonn

AUTHOR

Alexander Adamchuk (alex(AT)kolmogorov.com), Aug 10 2006

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Last modified February 17 09:16 EST 2012. Contains 206009 sequences.