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A091003
Expansion of (1-3*x^2)/((1-2*x)*(1+3*x)).
5
1, -1, 4, -10, 34, -94, 298, -862, 2650, -7822, 23722, -70654, 212986, -636910, 1914826, -5736286, 17225242, -51642958, 154994410, -464852158, 1394818618, -4183931566, 12552843274, -37656432670, 112973492314, -338912088334, 1016753042218
OFFSET
0,3
COMMENTS
Inverse binomial transform of A091000.
FORMULA
2^n = A091003(n) + 3*A091004(n) + 6*A091005(n).
a(n) = (2^n + 4*(-3)^n + 5*0^n)/10.
E.g.f.: (exp(2*x) + 4*exp(-3*x) + 5)/10. - G. C. Greubel, Feb 01 2019
MATHEMATICA
CoefficientList[Series[(1-3x^2)/((1-2x)(1+3x)), {x, 0, 30}], x] (* Harvey P. Dale, Dec 23 2014 *)
Join[{1}, LinearRecurrence[{-1, 6}, {-1, 4}, 30]] (* G. C. Greubel, Feb 01 2019 *)
PROG
(PARI) vector(30, n, n--; (2^n + 4*(-3)^n + 5*0^n)/10) \\ G. C. Greubel, Feb 01 2019
(Magma) [1] cat [(2^n + 4*(-3)^n)/10: n in [1..30]]; // G. C. Greubel, Feb 01 2019
(Sage) [1] + [(2^n + 4*(-3)^n)/10 for n in (1..30)] # G. C. Greubel, Feb 01 2019
(GAP) Concatenation([1], List([1..30], n -> (2^n + 4*(-3)^n)/10)) # G. C. Greubel, Feb 01 2019
CROSSREFS
Sequence in context: A066454 A301595 A022445 * A140725 A005630 A100507
KEYWORD
easy,sign
AUTHOR
Paul Barry, Dec 13 2003
STATUS
approved