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A245427
Primes of the form n^6 - n^5 + n^4 - n^3 + n^2 - n + 1.
2
43, 547, 909091, 1623931, 7027567, 10678711, 15790321, 22796593, 32222107, 81867661, 183458857, 234750601, 574995877, 2498207293, 6177695707, 7095062437, 9272716111, 13564461457, 19397579293, 24344094727, 50689400581, 81420308971, 137405657593, 149289169177
OFFSET
1,1
COMMENTS
All the terms in this sequence are primes, but none are congruent to 9 mod 10.
All terms == 1 (mod 7). - Robert Israel, Jul 22 2014
LINKS
EXAMPLE
n = 2: n^6 - n^5 + n^4 - n^3 + n^2 - n + 1 = 43, which is prime.
n = 10: n^6 - n^5 + n^4 - n^3 + n^2 - n + 1 = 909091, which is prime.
MATHEMATICA
Select[Table[n^6 - n^5 + n^4 - n^3 + n^2 - n + 1, {n, 200}], PrimeQ]
CROSSREFS
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Jul 21 2014
STATUS
approved