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A291245
p-INVERT of (0,1,0,1,0,1,...), where p(S) = 1 - 5 S + S^2.
2
5, 24, 120, 599, 2990, 14925, 74500, 371876, 1856265, 9265776, 46251265, 230868900, 1152410620, 5752399899, 28713814350, 143328549649, 715442152480, 3571217840400, 17826174791885, 88981552487776, 444162405876285, 2217091490069376, 11066885918992400
OFFSET
0,1
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.
FORMULA
G.f.: (5 - x - 5*x^2)/(1 - 5*x - x^2 + 5*x^3 + x^4).
a(n) = 5*a(n-1) + a(n-2) - 5*a(n-3) - a(n-4) for n >= 5.
MATHEMATICA
z = 60; s = x/(1 - x^2); p = 1 - 5 s - s^2;
Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000035 *)
Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A291245 *)
CROSSREFS
Sequence in context: A026784 A017977 A017978 * A255715 A163610 A055825
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Aug 28 2017
STATUS
approved