A108205 a(n) = 2*(n-1)*a(n-1)+(n-1)*a(n-2) with a(0)=0, a(1)=1.

0, 1, 2, 10, 66, 568, 6010, 75528, 1099462, 18195616, 337416246, 6930281080, 156177762466, 3831429672144, 101647482387802, 2899769522268472, 88517797903871190, 2878965845280173632, 99389641303891713718

Offset

0,3

Comments

This is also the (2,2) element of the product matrix after multiplying the unit matrix from the left by the matrices (0,1;j-1,2j-2) in the order j=2 to n.

Links

Table of n, a(n) for n=0..18.

Mathematica

M[n_] := {{0, 1}, {(n - 1), 2*(n - 1)}} v[1] = {0, 1} v[n_] := v[n] = M[n].v[n - 1] a = Table[Abs[v[n][[1]]], {n, 1, 25}]
nxt[{n_, a_, b_}]:={n+1, b, 2n*b+n*a}; NestList[nxt, {1, 0, 1}, 20][[;; , 2]] (* Harvey P. Dale, May 26 2023 *)

Crossrefs

Cf. A000166.

Sequence in context: A376226 A346417 A377529 * A228938 A245000 A108397

Adjacent sequences: A108202 A108203 A108204 * A108206 A108207 A108208

Keyword

nonn,easy

Author

Roger L. Bagula, Jun 15 2005

Extensions

Definition substituted by G. Detlefs' recurrence by the Associate Editors of the OEIS, Sep 28 2009

Status

approved