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A008991
Numerators of coefficients in expansion of sqrt(sin(x)/x) (even powers only).
5
1, -1, 1, -1, -67, -1, -64397, -113249, -3679787, -810304169, -6040635661561, -428305999661, -16827172241810597, -5620292762592913, -1550760014054450957, -4168373361283100017, -8551022502876237590534947
OFFSET
0,5
LINKS
Eric Weisstein's World of Mathematics, The Sinc Function.
FORMULA
sum(n>=0, A008991(n)/A008992(n) ) = A117017 - Johannes W. Meijer, Feb 10 2013
MAPLE
A008991 := n -> numer(coeff(taylor(sqrt(sin(x)/x), x, 2*n+2), x, 2*n)): seq(A008991(n), n=0..16); # Johannes W. Meijer, Feb 10 2013
MATHEMATICA
Numerator[CoefficientList[Series[Sqrt[Sin[x]/x], {x, 0, 50}], x][[1 ;; -1 ;; 2]]] (* G. C. Greubel, Jul 21 2018 *)
PROG
(Sage)
length = 16; T = taylor(sqrt(sin(x)/x), x, 0, 2*length+2)
[T.coefficient(x, 2*n).numerator() for n in (0..length)]
# Peter Luschny, Dec 13 2012
CROSSREFS
Denominators are in A008992.
Appears in A220002 and A220466.
Sequence in context: A295790 A246241 A337893 * A051323 A112506 A033387
KEYWORD
sign
STATUS
approved