A009201 - OEIS

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A009201

E.g.f. exp(sin(sin(x))).

1, 1, 1, -1, -7, -7, 73, 335, -687, -12367, -19471, 461119, 2839561, -15282199, -260138759, -15084017, 22560194593, 113205762401, -1856685484703, -23353924295169, 115492830956953, 3999727786726617, 5211807618131753, -646193037236457649

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,5

LINKS

Table of n, a(n) for n=0..23.

MATHEMATICA

With[{nn=30}, CoefficientList[Series[Exp[Sin[Sin[x]]], {x, 0, nn}], x] Range[ 0, nn]!] (* Harvey P. Dale, Dec 21 2018 *)

PROG

(Maxima)

a(n):=if n=0 then 1 else sum((sum((4^(j+1)*(sum((i-n/2+j)^(n-2*j+2*k)*(-1)^(i)*binomial(n-2*j, i), i, 0, (n/2-j)))*sum((-n/2+j-k+i)^n*binomial(n-2*j+2*k, i)*(-1)^(j-i), i, 0, (n/2-j+k)))/(n-2*j+2*k)!, k, 0, j))/(n-2*j)!, j, 0, (n-1)/2); /* Vladimir Kruchinin, Jun 20 2011 */

CROSSREFS

Sequence in context: A367456 A360367 A274908 * A219353 A269902 A269937

Adjacent sequences: A009198 A009199 A009200 * A009202 A009203 A009204

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved