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!)
A364708 Triangle of coefficient of the series reversion in t of the power series (exp(log(1+t*x)/x)-1)*exp(-t) as an e.g.f. 1

%I #38 Feb 03 2024 10:13:37

%S 1,1,1,2,6,1,6,35,22,1,24,225,310,65,1,120,1624,3885,1975,171,1,720,

%T 13132,47929,45080,10367,420,1,5040,118124,606060,909489,409416,48034,

%U 988,1,40320,1172700,7995455,17445645,13033398,3152520,204423,2259,1,362880,12753576,110917400,330281930,369520305,153751773,21587950,819120,5065,1

%N Triangle of coefficient of the series reversion in t of the power series (exp(log(1+t*x)/x)-1)*exp(-t) as an e.g.f.

%C T(n,k) is also the dimension of the operad FMan in arity n with k commutative products.

%C The sum of each row is n^(n-1).

%H Andrew Howroyd, <a href="/A364708/b364708.txt">Table of n, a(n) for n = 1..1275</a> (rows 1..50)

%H Paul Laubie, <a href="https://arxiv.org/abs/2401.17439">Hypertrees and embedding of the FMan operad</a>, arXiv:2401.17439 [math.QA], 2024.

%F T(n,0) = (n-1)!.

%F T(n,n-1) = 1.

%e Triangle T(n,k) begins:

%e n\k 0 1 2 3 4 ...

%e 1 1;

%e 2 1, 1;

%e 3 2, 6, 1;

%e 4 6, 35, 22, 1;

%e 5 24, 225, 310, 65, 1;

%e ...

%o (PARI) T(n) = my(x='x+O('x^(n+1))); [Vecrev(p) | p<-Vec(serlaplace( serreverse((exp(log(1+x*y)/y)-1)*exp(-x) )))]

%o {my(A=T(10)); for(n=1, #A, print(A[n]))} \\ _Andrew Howroyd_, Oct 20 2023

%Y Column k=0 is A000142(n-1).

%Y Row sums are A000169.

%Y Seems related to a signed version of A079510.

%K nonn,tabl,easy

%O 1,4

%A _Paul Laubie_, Oct 20 2023

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 September 2 08:40 EDT 2024. Contains 375613 sequences. (Running on oeis4.)