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A291218 p-INVERT of (0,1,0,1,0,1,...), where p(S) = 1 - S^5. 2
0, 0, 0, 0, 1, 0, 5, 0, 15, 1, 35, 10, 70, 55, 127, 220, 225, 715, 450, 2003, 1175, 5025, 3775, 11650, 12630, 25850, 40150, 57475, 118425, 134883, 325075, 345090, 840725, 952195, 2083888, 2722455, 5056055, 7765010, 12293890, 21615771, 30591685, 58293475 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

COMMENTS

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).

See A291219 for a guide to related sequences.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,5, 0,-10,1,10,0,-5,0,1)

FORMULA

G.f.: -(x^4/((-1 + x + x^2) (1 + x - 3 x^2 - 2 x^3 + 5 x^4 + 2 x^5 - 3 x^6 - x^7 + x^8))).

a(n) = 5*a(n-2) - 10*a(n-4) + a(n-5) + 10* a(n-6) - 5*a(n-8) + a(n-10) for n >= 11.

MATHEMATICA

z = 60; s = x/(1 - x^2); p = 1 - s^3;

Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000035 *)

Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291218 *)

LinearRecurrence[{0, 5, 0, -10, 1, 10, 0, -5, 0, 1}, {0, 0, 0, 0, 1, 0, 5, 0, 15, 1}, 50] (* Vincenzo Librandi, Aug 25 2017 *)

PROG

(MAGMA) I:=[0, 0, 0, 0, 1, 0, 5, 0, 15, 1]; [n le 10 select I[n] else 5*Self(n-2)-10*Self(n-4)+Self(n-5)+10*Self(n-6)-5*Self(n-8)+Self(n-10): n in [1..45]]; // Vincenzo Librandi, Aug 25 2017

CROSSREFS

Cf. A000035, A291000, A291219.

Sequence in context: A167297 A290867 A027635 * A321416 A226372 A093782

Adjacent sequences:  A291215 A291216 A291217 * A291219 A291220 A291221

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Aug 24 2017

STATUS

approved

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Last modified April 22 09:59 EDT 2021. Contains 343174 sequences. (Running on oeis4.)