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A012500 arctan(cos(x)*atan(x))=x-7/3!*x^3+173/5!*x^5-11779/7!*x^7... 0
1, -7, 173, -11779, 1474969, -296068991, 87094091589, -35308668668155, 18872654969343537, -12860552599622997751, 10882609077370643446493, -11195876625633675125480947, 13761866805554489099492092361 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

E.g.f.: atan(cos(x)*atan(x)) = Sum_{n>=0} a(n)*x^(2*n+1)/(2*n+1)!.

PROG

(PARI) a(n)=local(y); if(n<0, 0, y=x+x^2*O(x^(2*n)); (2*n+1)!*polcoeff(atan(cos(y)*atan(y)), 2*n+1))

CROSSREFS

Sequence in context: A157203 A178019 A075599 * A094257 A195887 A162082

Adjacent sequences:  A012497 A012498 A012499 * A012501 A012502 A012503

KEYWORD

sign

AUTHOR

Patrick Demichel (dml(AT)hpfrcu03.france.hp.com)

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Last modified February 15 23:34 EST 2012. Contains 205860 sequences.