login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A263338 Triangle read by rows: T(n,k) is the number of graphs with n vertices and Szeget index k. 0
1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 2, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 1, 1, 0, 1, 2, 2, 0, 0, 1, 1, 2, 5, 1, 2, 2, 2, 0, 0, 0, 2, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 1, 2, 2, 2, 3, 4, 1, 0, 1, 1, 3, 5, 2, 2, 3, 2, 1, 2, 2, 6, 6, 2, 5, 7, 10, 5, 5, 2, 6, 6, 3, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,18

COMMENTS

Row sums give A000088, n >= 1.

LINKS

Table of n, a(n) for n=1..100.

FindStat - Combinatorial Statistic Finder, The Szeged index of a graph.

EXAMPLE

Triangle begins:

1,

1,1,

1,1,0,1,1,

1,1,1,1,1,0,1,0,1,2,1,0,0,0,0,0,1,

1,1,1,1,2,1,1,0,1,2,2,0,0,1,1,2,5,1,2,2,2,0,0,0,2,0,0,0,1,1,0,0,0,0,0,0,1,

...

CROSSREFS

Cf. A000088.

Sequence in context: A025448 A015010 A016011 * A103522 A101108 A279280

Adjacent sequences:  A263335 A263336 A263337 * A263339 A263340 A263341

KEYWORD

nonn,tabf

AUTHOR

Christian Stump, Oct 15 2015

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 4 13:06 EST 2021. Contains 349526 sequences. (Running on oeis4.)