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A084861 Expansion of (1-3x+4x^2-3x^3+x^4)/(1-2x)^2. 1
1, 1, 4, 9, 21, 48, 108, 240, 528, 1152, 2496, 5376, 11520, 24576, 52224, 110592, 233472, 491520, 1032192, 2162688, 4521984, 9437184, 19660800, 40894464, 84934656, 176160768, 364904448, 754974720, 1560281088, 3221225472 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Partial sums give A084860. Binomial transform of signed version of A008795.

LINKS

Table of n, a(n) for n=0..29.

Index entries for linear recurrences with constant coefficients, signature (4,-4).

FORMULA

a(n) = 3(n+3)2^(n-4), n>2.

CROSSREFS

Sequence in context: A117880 A027973 A103040 * A122498 A132750 A297296

Adjacent sequences:  A084858 A084859 A084860 * A084862 A084863 A084864

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Jun 12 2003

STATUS

approved

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Last modified December 16 08:42 EST 2018. Contains 318158 sequences. (Running on oeis4.)