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A289560
Primes of the form k!4+256, where k!4 is the quadruple factorial number (A007662).
1
257, 277, 487, 1267389841, 50491808745015763381, 1008407509171875041482378381, 429215532868726286171043772444743140881, 4551830726072842264843919206776501006328381
OFFSET
1,1
LINKS
MATHEMATICA
MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];
Select[Table[MultiFactorial[i, 4] + 256, {i, 0, 100}], PrimeQ[#]&]
Select[Table[256+Times@@Range[n, 1, -4], {n, 200}], PrimeQ] (* Harvey P. Dale, Nov 04 2024 *)
CROSSREFS
Cf. A291349.
Sequence in context: A288411 A060879 A062382 * A256776 A252279 A105345
KEYWORD
nonn
AUTHOR
Robert Price, Sep 02 2017
STATUS
approved