A061485 Numerator of 1/(2n-1) + 3/(2n-3) + 5/(2n-5) + ...(2n-1)/1.

1, 10, 31, 988, 811, 19102, 131093, 1096792, 2420773, 95052434, 48911887, 4616289884, 5904218077, 36168951362, 534488973899, 269764710179504, 17133785963669, 34783298901958, 652516251742073, 2644314567590492

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