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A108209 a(n) = 5*(n-1)*a(n-1) -2*(n-1)*a(n-2) with a(0)=0, a(1)=2. 0
0, 2, 10, 92, 1320, 25664, 628400, 18544032, 640243520, 25313036288, 1127562249600, 55871851754240, 3048145476992000, 181547804177418240, 11721355489130393600, 815411545722159841280, 60804225264488076288000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This is also the negative of the (1,2) element of the product matrix after multiplying the unit matrix from the

left by the matrices (0,-2;j-1,5j-5) in the order j=2 to n.

LINKS

Table of n, a(n) for n=0..16.

MATHEMATICA

M[n_] := {{0, -2}, {(n - 1), 5*(n - 1)}} v[1] = {0, 1} v[n_] := v[n] = M[n].v[n - 1] a = Table[Abs[v[n][[1]]], {n, 1, 25}]

CROSSREFS

Cf. A000166.

Sequence in context: A108528 A181136 A182952 * A111773 A289020 A195415

Adjacent sequences:  A108206 A108207 A108208 * A108210 A108211 A108212

KEYWORD

nonn,easy

AUTHOR

Roger L. Bagula, Jun 15 2005

EXTENSIONS

Definition replaced by recurrence by the Associate Editors of the OEIS, Sep 28 2009

STATUS

approved

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Last modified August 14 13:42 EDT 2020. Contains 336481 sequences. (Running on oeis4.)