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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A050396 Exponential reversion of rooted trees A000081. 2
1, -1, 1, 1, -14, 64, -97, -1376, 15915, -68820, -467868, 11504693, -85105325, -490922106, 21504158897, -242026388646, -848338391966, 80509815160192, -1351044945506956, 1506218518200935, 472249651021870475, -11783220545826576339, 78093421491085905492 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,5
LINKS
N. J. A. Sloane, Transforms
MATHEMATICA
a[n:0|1] := n; a[n_] := a[n] = Sum[m a[m] a[n-k*m], {m, n-1}, {k, (n-1)/m}]/(n-1); length = 20; Range[length]! InverseSeries[Sum[a[n] x^n/n!, {n, 0, length}] + O[x]^(length+1)][[3]] (* Vladimir Reshetnikov, Nov 06 2015 *)
CROSSREFS
Cf. A050395.
Sequence in context: A239856 A214483 A275179 * A344597 A069964 A275127
KEYWORD
sign
AUTHOR
Christian G. Bower, Nov 15 1999
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 14:21 EDT 2024. Contains 371254 sequences. (Running on oeis4.)