

A287207


Numbers k such that k![6] + 2 is prime, where k![6] = A085158(k) = sextuple factorial.


1



0, 1, 3, 5, 9, 17, 27, 45, 51, 53, 93, 197, 213, 221, 245, 279, 845, 927, 2055, 2895, 3615, 5613, 12753, 15737, 17813, 18545, 22629, 47859, 48797
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,3


COMMENTS

a(30) > 50000.
The first 7 primes associated with this sequence: 3, 3, 5, 7, 29, 937, 229637.


LINKS

Table of n, a(n) for n=1..29.
C. Caldwell and H. Dubner (Eds): The top ten prime numbers: from the unpublished collections of R. Ondrejka (May 2001), Table 21 F, p. 75
Ken Davis, Status of Search for Multifactorial Primes.


MATHEMATICA

MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n  k, k]];
Select[Range[0, 50000], PrimeQ[MultiFactorial[#, 6] + 2] &]


CROSSREFS

Cf. A076185, A085158, A094144, A204657.
Sequence in context: A143105 A032679 A154607 * A298338 A018162 A077879
Adjacent sequences: A287204 A287205 A287206 * A287208 A287209 A287210


KEYWORD

nonn


AUTHOR

Robert Price, May 21 2017


STATUS

approved



