A289729 Primes of the form k!6-9, where k!6 is the sextuple factorial number (A085158).
7, 31, 631, 14071, 116471, 24663654391, 1282510028791, 17450008575991, 333247405883391991, 5444123475574783991
Offset: 1
Keywords
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..18
- Henri & Renaud Lifchitz, PRP Records.Search for n!6-9.
- Joe McLean, Interesting Sources of Probable Primes
- OpenPFGW Project, Primality Tester
Crossrefs
Cf. A289687.
Programs
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Mathematica
MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]]; Select[Table[MultiFactorial[i, 6] - 9, {i, 8, 100}], PrimeQ[#]&] Select[Table[Times@@Range[n,1,-6]-9,{n,8,100}],PrimeQ] (* Harvey P. Dale, Aug 21 2023 *)