A291687 Primes of the form k!4+4, where k!4 is the quadruple factorial number (A007662).

5, 7, 3469, 9949, 65839, 1514209, 5221129, 40883539, 151412629, 44358635479, 16713607661375629, 36453104912477522894629, 1027438963906784290227656915629, 7419136758370889359733910587728129, 4551830726072842264843919206776501006328129

Offset

1,1

Links

Robert Price, Table of n, a(n) for n = 1..18

Henri& Renaud Lifchitz, PRP Records.Search for n!4+4.

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, 4] + 4, {i, 0, 100}], PrimeQ[#]&]

Crossrefs

Cf. A291122.

Sequence in context: A370190 A176599 A309409 * A257774 A281386 A090817

Adjacent sequences: A291684 A291685 A291686 * A291688 A291689 A291690

Keyword

nonn

Author

Robert Price, Aug 29 2017

Status

approved