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A288717 Primes of the form k!7+1, where k!7 is the septuple factorial number (A114799). 1
2, 3, 5, 7, 19, 31, 61, 79, 12241, 19801, 29641, 76561, 379441, 2016841, 2756161, 1838865601, 4150656721, 337767408001, 956960801281, 21617114112001, 1534815101952001, 9590944392057601, 30891838760640001, 119715577952256001, 767275551364608001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Price, Table of n, a(n) for n = 1..46

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, 0, 100}], PrimeQ[#]&]

CROSSREFS

Cf. A156165.

Sequence in context: A048419 A087562 A154525 * A144561 A215156 A065724

Adjacent sequences:  A288714 A288715 A288716 * A288718 A288719 A288720

KEYWORD

nonn

AUTHOR

Robert Price, Jun 13 2017

STATUS

approved

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Last modified August 11 09:30 EDT 2020. Contains 336423 sequences. (Running on oeis4.)