A374652 a(n) = Sum_{k=1..n+1} (-1)^(k - 1)*(k + 1)*(n - k + 1)!.

-1, 5, 5, 39, 181, 1159, 8301, 67919, 621941, 6308679, 70223101, 851165119, 11160489861, 157411458359, 2376543620621, 38242755444399, 653435591570581, 11815320900966439, 225408497129888541, 4524816801601368479, 95339744251262894501, 2103888092422797642519

Offset

1,2

Comments

Residues mod 10 are 9, 5, 5, 9, 1, 9, 1, 9, 1, 9, 1, 9, 1, 9, 1, 9, 1, 9,...

Links

Table of n, a(n) for n=1..22.

Mathematica

t[n_] := Sum[(-1)^(k - 1) (k + 1)*(n - k + 1)!, {k, 1, n + 1}]
Table[t[n], {n, 1, 30}]

Crossrefs

Cf. A374651, A374653.

Sequence in context: A139386 A074947 A099757 * A271091 A271289 A271083

Adjacent sequences: A374649 A374650 A374651 * A374653 A374654 A374655

Keyword

sign

Author

Clark Kimberling, Jul 25 2024

Extensions

Definition corrected by Georg Fischer, Aug 27 2024

Status

approved