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A103421 Number of compositions of n in which the greatest part is odd. 2
1, 1, 2, 3, 7, 14, 30, 62, 129, 263, 534, 1076, 2160, 4318, 8612, 17145, 34097, 67764, 134638, 267506, 531606, 1056812, 2101854, 4182462, 8327263, 16588973, 33066080, 65945522, 131588128, 262702054, 524699094, 1048433468, 2095744336 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
G.f.: Sum((1-x)^2*x^(2*n-1)/((1-2*x+x^(2*n-1))*(1-2*x+x^(2*n))), n=1..infinity).
a(n) + A103422(n) = 2^(n-1). - R. J. Mathar, Mar 24 2018
MATHEMATICA
Rest[ CoefficientList[ Series[ Expand[ Sum[(1 - x)^2*x^(2n - 1)/((1 - 2x + x^(2n - 1))*(1 - 2x + x^(2n))), {n, 35}]], {x, 0, 35}], x]] (* Robert G. Wilson v, Feb 05 2005 *)
CROSSREFS
Sequence in context: A192570 A019595 A112884 * A205484 A151530 A180752
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Feb 04 2005
EXTENSIONS
More terms from Robert G. Wilson v, Feb 05 2005
STATUS
approved

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Last modified June 15 08:58 EDT 2024. Contains 373402 sequences. (Running on oeis4.)