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A164661
Denominators of row sums of triangle of rationals A164658/A164659. Definite integral of Chebyshev polynomials of the first kind: Integral_{x=0..1} T(n,x).
7
1, 2, 3, 2, 15, 6, 35, 6, 63, 10, 99, 10, 143, 14, 195, 14, 255, 18, 323, 18, 399, 22, 483, 22, 575, 26, 675, 26, 783, 30, 899, 30, 1023, 34, 1155, 34, 1295, 38, 1443, 38, 1599, 42, 1763, 42, 1935, 46, 2115, 46, 2303, 50, 2499, 50, 2703, 54, 2915, 54, 3135, 58, 3363, 58, 3599
OFFSET
0,2
COMMENTS
The numerators are given in A164660.
See the W. Lang link under A164660 for a list of the first rationals.
FORMULA
a(n) = denominator(Sum_{m=1..n+1} IT(n,m)), n>=0, with IT(n,m):= A164658(n,m)/A164659(n,m) (coefficient triangle from the indefinite integral Integral_{x} T(n,x), n>=0, in lowest terms).
EXAMPLE
Rationals A164660(n)/a(n) = [1, 1/2, -1/3, -1/2, -1/15, 1/6, -1/35, -1/6, -1/63, 1/10, -1/99, ...].
CROSSREFS
Sequence in context: A181350 A174111 A367566 * A104507 A101033 A136454
KEYWORD
nonn,easy,frac
AUTHOR
Wolfdieter Lang, Oct 16 2009
STATUS
approved