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 A099235 A quadrisection of 1/(1-x-x^5). 2
 1, 1, 5, 15, 45, 140, 431, 1326, 4085, 12580, 38740, 119305, 367411, 1131476, 3484490, 10730820, 33046585, 101770120, 313410816, 965178576, 2972359720, 9153665985, 28189589705, 86812537085, 267347509271, 823322219501 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A row of A099233. LINKS Harvey P. Dale, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (1,4,6,4,1). FORMULA G.f.: 1/(1-x(1+x)^4); a(n)=sum{k=0..n, binomial(4(n-k), k)}; a(n)=a(n-1)+4a(n-2)+6a(n-3)+4a(n-4)+a(n-5); a(n)=A003520(4n). MATHEMATICA Take[CoefficientList[Series[1/(1-x-x^5), {x, 0, 100}], x], {1, -1, 4}] (* or *) LinearRecurrence[{1, 4, 6, 4, 1}, {1, 1, 5, 15, 45}, 30] (* Harvey P. Dale, Mar 06 2015 *) CROSSREFS Sequence in context: A084244 A005030 A200664 * A207096 A035069 A176611 Adjacent sequences:  A099232 A099233 A099234 * A099236 A099237 A099238 KEYWORD easy,nonn AUTHOR Paul Barry, Oct 08 2004 STATUS approved

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Last modified December 3 22:32 EST 2021. Contains 349468 sequences. (Running on oeis4.)