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A109438 a(n) = 5a(n-1) - 5a(n-2) + a(n-3) + 2*(-1)^(n+1), alternatively a(n) = 3a(n-1) + 3a(n-2) - a(n-3). 1
1, 5, 18, 68, 253, 945, 3526, 13160, 49113, 183293, 684058, 2552940, 9527701, 35557865, 132703758, 495257168, 1848324913, 6898042485, 25743845026, 96077337620, 358565505453, 1338184684193, 4994173231318, 18638508241080 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

See A109437 for comments.

LINKS

Table of n, a(n) for n=0..23.

FORMULA

G.f. (1+2*x)/((x+1)*(x^2-4*x+1))

PROG

Floretion Algebra Multiplication Program, FAMP Code: (-1)^(n)jbasejfor[ + .5'ii' + .5'kk' + .5'ij' + .5'ji' + .5'jk' + .5'kj'] 1vesfor = (-1, -1, -1, -1, )

CROSSREFS

Cf. A109437, A001834, A102871.

Sequence in context: A158879 A279488 A199843 * A164051 A134764 A188177

Adjacent sequences:  A109435 A109436 A109437 * A109439 A109440 A109441

KEYWORD

easy,nonn

AUTHOR

Creighton Dement, Jun 28 2005

STATUS

approved

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Last modified November 20 04:05 EST 2017. Contains 294959 sequences.