A288889 Primes of the form k!3+3, where k!3 is the triple factorial number (A007661).

5, 7, 13, 31, 83, 283, 883, 3643, 12323, 58243, 1106563, 4188803, 2504902403, 17041024003, 72642169603, 2324549427203, 126757680265216003, 38900816605808456499200003, 26070192823309041523916800003, 254451773522587035734629406212096000003

Offset

1,1

Links

Robert Price, Table of n, a(n) for n = 1..24

Henri& Renaud Lifchitz, PRP Records.Search for n!3+3.

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, 3] + 3, {i, 0, 100}], PrimeQ[#]&]

Crossrefs

Cf. A007661, A249400.

Sequence in context: A179625 A141191 A101782 * A168609 A266951 A102903

Adjacent sequences: A288886 A288887 A288888 * A288890 A288891 A288892

Keyword

nonn

Author

Robert Price, Jun 18 2017

Status

approved