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 A009446 E.g.f. sin(x*cos(x)) (odd powers only) 5
 1, -4, 36, -848, 23824, -871872, 44942912, -2860930816, 213856723200, -19099352929280, 2010469524579328, -242177953175506944, 32998102512641970176, -5069553933584348397568, 870871673923373487243264 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(n)=(-1)^(n)*sum(k=0..n, binomial(2*n+1,2*k+1)*((sum(i=0..k, (2*k+1-2*i)^(2*n-2*k)*binomial(2*k+1,i))))/(2^(2*k))). - Vladimir Kruchinin, Jun 18 2011 MATHEMATICA With[{nn=30}, Take[CoefficientList[Series[Sin[x Cos[x]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Oct 04 2017 *) PROG (Maxima) a(n):=(-1)^(n)*sum(binomial(2*n+1, 2*k+1)*((sum((2*k+1-2*i)^(2*n-2*k)*binomial(2*k+1, i), i, 0, ((k)))))/(2^(2*k)), k, 0, n); /* Vladimir Kruchinin, Jun 18 2011 */ CROSSREFS Sequence in context: A145565 A214669 A126152 * A134052 A127901 A061742 Adjacent sequences:  A009443 A009444 A009445 * A009447 A009448 A009449 KEYWORD sign AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 STATUS approved

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Last modified August 26 05:23 EDT 2019. Contains 326328 sequences. (Running on oeis4.)