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A052251 Column 3 of A052250. 2
1, 3, 6, 13, 27, 63, 148, 363, 912, 2330, 6036, 15825, 41865, 111636, 299736, 809513, 2197728, 5994219, 16416748, 45129396, 124479270, 344403494, 955557780, 2658061560, 7411457963, 20710700277, 57992124810, 162691293718, 457219737027, 1287065977413 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

COMMENTS

Also expansion of cube of g.f. for A051573. - Alois P. Heinz, Oct 23 2009

LINKS

Alois P. Heinz, Table of n, a(n) for n = 3..700

FORMULA

a(n) ~ c * d^n / n^(3/2), where d = A051491 = 2.9557652856519949747148175241..., c = 0.195489104191039910520879642... . - Vaclav Kotesovec, Sep 05 2014

MAPLE

with(numtheory): A81:= proc(n) option remember; `if`(n<2, n, (add(add(d*A81(d), d=divisors(j)) *A81(n-j), j=1..n-1))/ (n-1)) end: b:= proc(n) option remember; -`if`(n<0, 1, add(b(n-i) *A81(i+1), i=1..n+1)) end: B:= proc(n) add(b(i) *x^i, i=0..n) end: a:= n-> coeff(B(n)^3, x, n-3): seq(a(n), n=3..35); # Alois P. Heinz, Oct 23 2009

CROSSREFS

Cf. A051573, A000081. - Alois P. Heinz, Oct 23 2009

Cf. A051491.

Sequence in context: A131246 A183314 A036886 * A032253 A125777 A103788

Adjacent sequences:  A052248 A052249 A052250 * A052252 A052253 A052254

KEYWORD

nonn

AUTHOR

David Broadhurst, Feb 05 2000

EXTENSIONS

More terms from Alois P. Heinz, Oct 23 2009

STATUS

approved

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Last modified October 16 16:18 EDT 2019. Contains 328101 sequences. (Running on oeis4.)