The OEIS is supported by the many generous donors to the OEIS Foundation.

A363465
G.f. A(x) satisfies: A(x) = x + x^2 * exp( Sum_{k>=1} A(x^k)^3 / (k*x^(2*k)) ).
2
1, 1, 1, 4, 10, 35, 113, 405, 1447, 5369, 20143, 76908, 296800, 1157784, 4554142, 18050308, 72003513, 288880549, 1164867528, 4718481975, 19190711729, 78338352168, 320851617424, 1318115448886, 5430133003281, 22427330328214, 92847100210382, 385217596191075, 1601483701650310
OFFSET
1,4
MATHEMATICA
nmax = 29; A[_] = 0; Do[A[x_] = x + x^2 Exp[Sum[A[x^k]^3/(k x^(2 k)), {k, 1, nmax}]] + O[x]^(nmax + 1)//Normal, nmax + 1]; CoefficientList[A[x], x] // Rest
a[1] = a[2] = 1; f[n_] := f[n] = Sum[a[k] a[n - k], {k, 1, n - 1}]; g[n_] := g[n] = Sum[a[k] f[n - k], {k, 1, n - 1}]; a[n_] := a[n] = (1/(n - 2)) Sum[Sum[d g[d + 2], {d, Divisors[k]}] a[n - k], {k, 1, n - 2}]; Table[a[n], {n, 1, 29}]
CROSSREFS
Sequence in context: A222631 A030003 A339845 * A234009 A198324 A149175
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jun 03 2023
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 20 02:18 EDT 2024. Contains 376016 sequences. (Running on oeis4.)