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A108208 a(n) = 4*(n-1)*a(n-1) -2*(n-1)*a(n-2), with a(0)=0, a(1)=2. 0
0, 2, 8, 56, 624, 9536, 184480, 4313088, 118183744, 3712870400, 131536027008, 5187183672320, 225342288987904, 10691937463283712, 550121848577067520, 30507449271343837184, 1813943300823318205440, 115116132876009362358272 (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-1,4j-4) in the order j=2 to n.

LINKS

Table of n, a(n) for n=0..17.

MATHEMATICA

M[n_] := {{0, -2}, {(n - 1), 4*(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: A243953 A005439 A128814 * A203199 A135079 A084872

Adjacent sequences:  A108205 A108206 A108207 * A108209 A108210 A108211

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 December 20 04:40 EST 2014. Contains 252241 sequences.