A216369 a(n) = !(n-1) mod n.

0, 0, 1, 2, 4, 2, 6, 6, 1, 6, 1, 2, 10, 8, 4, 6, 13, 8, 9, 6, 13, 10, 21, 14, 14, 16, 10, 22, 17, 26, 2, 6, 1, 4, 34, 26, 5, 10, 10, 6, 4, 8, 16, 10, 19, 2, 18, 38, 48, 36, 13, 42, 13, 44, 34, 22, 28, 12, 28, 26, 22, 60, 55, 38, 49, 32, 65, 38, 67, 36, 68, 62

Offset: 1

Author

Michel Lagneau, Sep 05 2012

Keywords

• nonn

Comments

!n is a subfactorial number (A000166).

Examples

			a(7)=6 because !(7-1) = 265, and 265 == 6 mod 7.
		

Links

• Indranil Ghosh, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000166, A124625.

Programs

Maple

with(numtheory): f:=n->sum(n!*(((-1)^k)*1/k!), k=0..n):for n from 1 to 150 do:  x:=irem(f(n-1),n): printf(`%d, `, x):od: