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A249999 Expansion of 1/((1-x)^2*(1-2*x)*(1-3*x)). 1
1, 7, 32, 122, 423, 1389, 4414, 13744, 42245, 128771, 390396, 1179366, 3554467, 10696153, 32153978, 96592988, 290041089, 870647535, 2612991160, 7841070610, 23527406111, 70590606917, 211788597942, 635399348232, 1906265153533, 5718929678299, 17157057470324, 51471709281854 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..27.

Index entries for linear recurrences with constant coefficients, signature (7,-17,17,-6).

FORMULA

a(n) = 9/4 - 2^(n+3) + n/2 + 3^(n+3)/4. - R. J. Mathar, Jan 09 2015

CROSSREFS

Cf. A000392 (first differences), A094705, A243869, A249997.

Sequence in context: A133107 A178851 A213163 * A034360 A268745 A199845

Adjacent sequences:  A249996 A249997 A249998 * A250000 A250001 A250002

KEYWORD

nonn,easy

AUTHOR

Alex Ratushnyak, Dec 28 2014

STATUS

approved

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Last modified November 18 07:01 EST 2018. Contains 317279 sequences. (Running on oeis4.)