OFFSET
1,1
COMMENTS
Corresponding primes are: 11, 389, 919, 8549258359016359, 17694587964658118355578965371540271859, ...
a(21) > 10^5.
Terms > 17 correspond to probable primes.
LINKS
Henri & Renaud Lifchitz, PRP Records. Search for n!6-16.
Joe McLean, Interesting Sources of Probable Primes
OpenPFGW Project, Primality Tester
EXAMPLE
17!6 - 16 = 17*11*5 - 16 = 919 is prime, so 17 is in the sequence.
MATHEMATICA
MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
Select[Range[6, 50000], PrimeQ[MultiFactorial[#, 6] - 16] &]
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert Price, Jul 09 2017
EXTENSIONS
a(18)-a(20) from Robert Price, Aug 03 2018
STATUS
approved