A306738 Number of permutations of [n] allowing i->i+j (mod n), j=0..ceiling(n/2)-1.

1, 1, 1, 2, 2, 13, 20, 144, 264, 2783, 6208, 79118, 204448, 3182225, 9411840, 170576156, 566725760, 11804363619, 43573050368, 1023207993178, 4152609019392, 108681408827381, 481065936784384, 13880706183899752

Offset: 0

Author

Alois P. Heinz, Mar 06 2019

Keywords

• nonn

Crossrefs

Cf. A008305.

Formula

a(n) = A008305(n,ceiling(n/2)).