OFFSET
1,4
LINKS
Hisanori Mishima, Appendix 1. Factorization results for n!+1
Eric Weisstein's World of Mathematics, Wilson's Theorem
FORMULA
EXAMPLE
a(7) = omega((prime(7)-1)! + 1) = omega((17-1)! + 1) = omega(16! + 1) = omega(20922789888000 + 1) = omega(20922789888001) = 5, as 20922789888001 = 17 * 61 * 137 * 139 * 1059511 = prime(7)*prime(18)*prime(33)*prime(34)*prime(82801).
MATHEMATICA
Table[ Length[ FactorInteger[ (Prime[ n ] - 1)! + 1 ] ], {n, 1, 15} ]
PROG
(PARI) a(n) = omega((prime(n)-1)! + 1); \\ Jinyuan Wang, Apr 01 2020
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Reinhard Zumkeller, Jan 20 2002
EXTENSIONS
More terms from Robert G. Wilson v, Jan 21 2002
a(27)-a(34) from Jinyuan Wang, Apr 01 2020
STATUS
approved