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A061485 Numerator of 1/(2n-1) + 3/(2n-3) + 5/(2n-5) + ...(2n-1)/1. 0
1, 10, 31, 988, 811, 19102, 131093, 1096792, 2420773, 95052434, 48911887, 4616289884, 5904218077, 36168951362, 534488973899, 269764710179504, 17133785963669, 34783298901958, 652516251742073, 2644314567590492 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

a(1)=1, a(2)=10 as (1/3 + 3/1) = 10/3, a(3)=31 as 1/5 + 3/3 + 5/1 = 31/5.

PROG

(Rexx)

numeric digits 100; do N = 1 to 22; X = 1; do K = 1 to N; X = X*(2*K-1); end K; Y = 0; do K = 1 to N; Y = Y +(2*K-1)*X/(2*N-(2*K-1)); end K; say Y / GCD(X, Y); end; N

CROSSREFS

Sequence in context: A097236 A332254 A280202 * A136335 A008422 A063926

Adjacent sequences:  A061482 A061483 A061484 * A061486 A061487 A061488

KEYWORD

nonn,frac,easy

AUTHOR

Amarnath Murthy, May 06 2001

EXTENSIONS

Corrected and extended by Frank Ellermann

STATUS

approved

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Last modified September 26 05:07 EDT 2021. Contains 347664 sequences. (Running on oeis4.)