A121618 Nexus primes of order 7 or primes of form n^7 - (n-1)^7 = A022523(n-1).

127, 14197, 543607, 1273609, 2685817, 5217031, 16344637, 141903217, 1928294551, 8258704609, 14024867221, 22815424087, 30914273881, 91154730577, 116160677851, 183510024391, 280667317267, 552932810431, 1517045588059

Offset: 1

Author

Alexander Adamchuk, Aug 10 2006

Keywords

• nonn
• easy

Comments

Indices n such that Nexus number of 7 order (or A022523(n-1) = n^7 - (n-1)^7) is prime are listed in A121619(n) = {2,4,7,8,9,10,12,17,26, 33,36,39,41,49,51,55,59,66,78,79,80,88,96,98,...}. a(1) = 127 is Mersenne prime A000668(4).

Links

• Vladimir Pletser, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A022523, A000040, A000043, A000668, A002407, A121616, A121618, A121619, A121620.

Programs

Mathematica

Select[Table[n^7 - (n-1)^7, {n,1,200}],PrimeQ]
Select[Differences[Range[100]^7],PrimeQ] (* Harvey P. Dale, Mar 27 2025 *)

PARI

select(isprime,vector(1000,n,n^7-(n-1)^7)) \\ Charles R Greathouse IV, May 15 2013