a(1) = 1; for n>1, a(n) = n*a(n-1) - 1 if n is a prime else a(n) = n*a(n-1) + 1.
A093464
a(1) = 1; for n>1, a(n) = n*a(n-1) - 1 if n is a prime else a(n) = n*a(n-1) + 1.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =9a(4) =44a(5) =265a(6) =1854a(7) =14833a(8) =133498a(9) =1334981a(10) =14684790a(11) =176217481a(12) =2290827252a(13) =32071581529a(14) =481073722936
External references
- oeis: A093464