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!)
A346779 Number of Halin graphs on n nodes. 2

%I #19 May 20 2023 11:46:54

%S 0,0,0,1,1,2,2,4,6,13,22,50,106,252,589,1475,3669,9435,24345,63837,

%T 168234,447562,1196390,3218221

%N Number of Halin graphs on n nodes.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HalinGraph.html">Halin Graph</a>

%H Peter J. Taylor, <a href="/A346779/a346779.py.txt">Python program</a>

%e a(4) = 1 (K_4)

%e a(5) = 1 (W_5)

%e a(6) = 2 (3-prism graph, W_6)

%e a(7) = 2 (W_7 and one other)

%e a(8) = 4 (W_8 and 3 others)

%o (Python) # See Taylor link

%K nonn,more

%O 1,6

%A _Eric W. Weisstein_, Aug 03 2021

%E a(13) from _Eric W. Weisstein_, Aug 16 2021

%E a(14) from _Eric W. Weisstein_, Sep 29 2021

%E a(15)-a(24) from _Peter J. Taylor_, May 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 July 24 22:37 EDT 2024. Contains 374585 sequences. (Running on oeis4.)