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 A009529 Sin(tanh(x)*tan(x))/2 = Sum a(n)*x^(4*n+2)/(4*n+2)!. 0
 1, -4, -79664, -627244864, -10054978651904, -281464457981584384, -9106562752258155720704, 743620567656757236530855936, 627496952440053395297142177857536 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS EXAMPLE sin(tanh(x)*tan(x))/2 = (1/2)*x^2 - (1/180)*x^6 - (4979/226800)*x^10 - (9800701/1362160800)*x^14 - (39277260359/ 25009272288000)*x^18 + ..., and (say) -(4979/226800)*10! = -79664 = a(2). MATHEMATICA Sin[ Tanh[ x ]*Tan[ x ] ]/2 (* [ x^(4n+2) ] *) CROSSREFS Cf. A012667. Sequence in context: A102200 A257769 A066544 * A339450 A273231 A239021 Adjacent sequences: A009526 A009527 A009528 * A009530 A009531 A009532 KEYWORD sign AUTHOR EXTENSIONS Extended with signs Mar 1997 Edited by N. J. A. Sloane, Apr 02 2017 STATUS approved

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Last modified November 29 13:55 EST 2022. Contains 358430 sequences. (Running on oeis4.)