OFFSET
1,1
COMMENTS
Corresponding primes are: 3, 31, 67, 911, 21481, 43201, 623621, 1339951, ...
a(41) > 10^5.
Terms > 43 correspond to probable primes.
LINKS
Henri & Renaud Lifchitz, PRP Records. Search for n!6-24.
Joe McLean, Interesting Sources of Probable Primes
OpenPFGW Project, Primality Tester
EXAMPLE
13!6 - 4 = 13*7*1 - 24 = 67 is prime, so 13 is in the sequence.
MATHEMATICA
MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
Select[Range[9, 50000], PrimeQ[MultiFactorial[#, 6] - 24] &]
Select[Range[8, 5000], PrimeQ[Times@@Range[#, 1, -6]-24]&] (* Harvey P. Dale, Dec 01 2018 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert Price, Jul 09 2017
EXTENSIONS
a(37)-a(40) from Robert Price, Aug 03 2018
STATUS
approved