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 A012207 arcsinh(arctan(arctan(x)))=x-5/3!*x^3+137/5!*x^5-9141/7!*x^7... 0
 1, -5, 137, -9141, 1130993, -225155941, 66037540345, -26862446793685, 14500070037397089, -10041538909269213637, 8686453887771982767337, -9185311291945403768547829, 11662015255583014905028727633 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Table of n, a(n) for n=0..12. MATHEMATICA With[{nn=30}, Take[CoefficientList[Series[ArcSinh[ArcTan[ArcTan[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jul 16 2013 *) CROSSREFS Sequence in context: A339566 A012215 A012142 * A192640 A192641 A192642 Adjacent sequences: A012204 A012205 A012206 * A012208 A012209 A012210 KEYWORD sign AUTHOR Patrick Demichel (patrick.demichel(AT)hp.com) EXTENSIONS Definition clarified by Harvey P. Dale, Jul 16 2013 STATUS approved

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Last modified February 20 17:43 EST 2024. Contains 370215 sequences. (Running on oeis4.)