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A289757 Primes of the form k!7-1, where k!7 is the septuple factorial number (A114799). 1
2, 3, 5, 7, 17, 29, 43, 59, 97, 509, 1559, 12239, 198719, 379439, 633599, 1136678399, 33739804799, 99298742399, 1990648483199, 59126328543388935628799, 3797826416991538753535999, 2409161546475779555007420356689919999, 9325555101161759039183007326207999999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Price, Table of n, a(n) for n = 1..34

Henri & Renaud Lifchitz, PRP Records.Search for n!7-1.

Joe McLean, Interesting Sources of Probable Primes

OpenPFGW Project, Primality Tester

MATHEMATICA

MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];

Select[Table[MultiFactorial[i, 7] - 1, {i, 2, 100}], PrimeQ[#]&]

CROSSREFS

Cf. A156167.

Sequence in context: A107439 A262836 A178382 * A030480 A048418 A074788

Adjacent sequences:  A289754 A289755 A289756 * A289758 A289759 A289760

KEYWORD

nonn

AUTHOR

Robert Price, Jul 11 2017

STATUS

approved

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Last modified October 15 21:38 EDT 2021. Contains 348034 sequences. (Running on oeis4.)