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!)
A318865 Number of rooted trees with n nodes such that eight equals the maximal number of isomorphic subtrees extending from the same node. 2

%I #5 Sep 05 2018 08:42:30

%S 0,1,1,3,8,22,60,167,465,1307,3682,10422,29593,84291,240663,688685,

%T 1974519,5670969,16312391,46987389,135514781,391278211,1130924824,

%U 3271850658,9473951229,27454745755,79620703854,231064697016,670994912068,1949683485967,5668279789793

%N Number of rooted trees with n nodes such that eight equals the maximal number of isomorphic subtrees extending from the same node.

%H Alois P. Heinz, <a href="/A318865/b318865.txt">Table of n, a(n) for n = 8..2137</a>

%p h:= proc(n, m, t, k) option remember; `if`(m=0, binomial(n+t, t),

%p `if`(n=0, 0, add(h(n-1, m-j, t+1, k), j=1..min(k, m))))

%p end:

%p b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,

%p add(b(n-i*j, i-1, k)*h(A(i, k), j, 0, k), j=0..n/i)))

%p end:

%p A:= (n, k)-> `if`(n<2, n, b(n-1$2, k)):

%p a:= n-> (k-> A(n, k)-A(n, k-1))(8):

%p seq(a(n), n=8..38);

%Y Column k=8 of A318758.

%K nonn

%O 8,4

%A _Alois P. Heinz_, Sep 04 2018

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 April 27 18:09 EDT 2024. Contains 372020 sequences. (Running on oeis4.)