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A220703 Numbers n such that n^7 + 7*n + 7^n is prime. 1
2, 3, 17, 74, 120, 212, 528, 2348 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..8.

MATHEMATICA

Select[Range[5000], PrimeQ[#^7 + 7*# + 7^#]&]

PROG

(PARI) is(n)=ispseudoprime(n^7+7*n+7^n) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A220528.

Sequence in context: A201455 A085874 A055739 * A342547 A245799 A056794

Adjacent sequences:  A220700 A220701 A220702 * A220704 A220705 A220706

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Jan 07 2013

STATUS

approved

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Last modified June 15 12:29 EDT 2021. Contains 345048 sequences. (Running on oeis4.)