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A134828 Numerator of moments of Chebyshev U- (or S-) polynomials. +0
2
1, 0, 1, 0, 1, 0, 5, 0, 7, 0, 21, 0, 33, 0, 429, 0, 715, 0, 2431, 0, 4199, 0, 29393, 0, 52003, 0, 185725, 0, 334305, 0, 9694845, 0, 17678835, 0, 64822395, 0, 119409675, 0, 883631595, 0, 1641030105, 0, 6116566755, 0, 11435320455, 0, 171529806825, 0 (list; graph; listen)
OFFSET

0,7

COMMENT

The denominators are given in A134829.

LINKS

W. Lang, Rationals and more.

FORMULA

a(n)= numerator(r(n)) with r(n):=int((2/Pi)*sqrt(1-x^2)*x^n,x=-1..+1), n>=0.

a(n)=0 if n is odd, a(n)=numerator(C(n/2)/2^n) if n is even, with the Catalan numbers C(n):=A000108(n).

EXAMPLE

Rationals: [1, 0, 1/4, 0, 1/8, 0, 5/64, 0, 7/128, 0, 21/512, 0, 33/1024, 0,...].

CROSSREFS

Cf. A098597 (coincides with numerators for even n).

Sequence in context: A069206 A091685 A062824 this_sequence A070595 A021873 A020801

Adjacent sequences: A134825 A134826 A134827 this_sequence A134829 A134830 A134831

KEYWORD

nonn,easy,frac

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Jan 21 2008

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Last modified August 19 23:53 EDT 2008. Contains 142930 sequences.


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