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A091005
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Expansion of x^2/((1-2x)(1+3x)).
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5
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0, 0, 1, -1, 7, -13, 55, -133, 463, -1261, 4039, -11605, 35839, -105469, 320503, -953317, 2876335, -8596237, 25854247, -77431669, 232557151, -697147165, 2092490071, -6275373061, 18830313487, -56482551853, 169464432775, -508359743893, 1525146340543
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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COMMENTS
| 2^n=A091003(n)+3*A091004(n)+6*A091005(n). Inverse binomial transform of A091002.
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FORMULA
| a(n)=2^n/10-4(-3)^n/15+0^n/6
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MATHEMATICA
| a[n_]:=(MatrixPower[{{1, 4}, {1, -2}}, n].{{1}, {1}})[[2, 1]]; Table[a[n], {n, 0, 40}] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Feb 19 2010]
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CROSSREFS
| Cf. A015441.
Sequence in context: A112540 A193489 A015441 * A183180 A133664 A143794
Adjacent sequences: A091002 A091003 A091004 * A091006 A091007 A091008
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KEYWORD
| easy,sign
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Dec 13 2003
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