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A061161 Numerators in expansion of Euler transform of b(n) = 1/4. 3
1, 1, 13, 55, 1235, 4615, 55801, 200343, 8977475, 36804235, 367235363, 1444888289, 32062742231, 120729974115, 1205864254225, 5201022002071, 395884671433315, 1603069490974835, 15989295873680415, 64312573140322525, 1250332447587844829, 5262481040435242585 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Denominators of c(n) are 2^A004134(n).

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Geoffrey B. Campbell, A Zujev, Some almost partition theoretic identities, Preprint, 2016

N. J. A. Sloane, Transforms

FORMULA

Numerators of c(n), where c(n)=1/(4*n)*Sum_{k=1..n} c(n-k)*sigma(k), n>0, c(0)=1.

MAPLE

b:= proc(n) option remember; `if`(n=0, 1, add(add(

      d/4, d=numtheory[divisors](j))*b(n-j), j=1..n)/n)

    end:

a:= n-> numer(b(n)):

seq(a(n), n=0..30);  # Alois P. Heinz, Jul 28 2017

CROSSREFS

Cf. A000712, A061159, A061160.

Sequence in context: A051798 A206372 A290396 * A212053 A264853 A210290

Adjacent sequences:  A061158 A061159 A061160 * A061162 A061163 A061164

KEYWORD

easy,nonn,frac

AUTHOR

Vladeta Jovovic, Apr 17 2001

STATUS

approved

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Last modified February 22 21:55 EST 2018. Contains 299469 sequences. (Running on oeis4.)