login
A329166
Numbers k such that k![4] - 16 is prime, where k![4] = A007662(k) = quadruple factorial.
0
7, 9, 13, 15, 17, 29, 31, 35, 39, 105, 109, 147, 173, 239, 287, 293, 505, 711, 837, 947, 1015, 1025, 1977, 2917, 4035, 4935, 5935, 7693, 10911, 11367, 12029, 14155, 15221, 17921, 17961, 20521, 23053, 32821, 45147, 45351, 68057, 78315
OFFSET
1,1
COMMENTS
a(43) > 10^5.
The first 5 primes associated with this sequence are: 5, 29, 569, 3449, 9929.
LINKS
MATHEMATICA
MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
Select[Range[1000], (x = MultiFactorial[#, 4] - 16; x > 0 && PrimeQ[x]) &]
CROSSREFS
Sequence in context: A051913 A180645 A196091 * A222945 A129069 A258616
KEYWORD
nonn
AUTHOR
Robert Price, Nov 06 2019
STATUS
approved