A241706
Number of simple connected graphs on n nodes with diameter 2.
Original entry on oeis.org
0, 0, 1, 4, 14, 59, 373, 4154, 91518, 4116896
Offset: 1
- Travis Hoppe and Anna Petrone, Encyclopedia of Finite Graphs
- Travis Hoppe and Anna Petrone, Integer sequence discovery from small graphs, arXiv preprint arXiv:1408.3644 [math.CO], 2014.
- Peter Steinbach, Field Guide to Simple Graphs, Volume 1, Part 17 [But beware errors] (For Volumes 1, 2, 3, 4 of this book see A000088, A008406, A000055, A000664, respectively.)
- Eric Weisstein's World of Mathematics, Graph Diameter
A294522
Triangle read by rows: T(n,k) is the number of simple connected graphs on n nodes with diameter k (0<=k
Original entry on oeis.org
1, 0, 1, 0, 1, 1, 0, 1, 4, 1, 0, 1, 14, 5, 1, 0, 1, 59, 43, 8, 1, 0, 1, 373, 387, 82, 9, 1, 0, 1, 4154, 5797, 1027, 125, 12, 1, 0, 1, 91518, 148229, 19320, 1818, 180, 13, 1, 0, 1, 4116896, 6959721, 598913, 37856, 2928, 239, 16, 1
Offset: 1
Triangle begins:
1;
0, 1;
0, 1, 1;
0, 1, 4, 1;
0, 1, 14, 5, 1;
0, 1, 59, 43, 8, 1;
0, 1, 373, 387, 82, 9, 1;
0, 1, 4154, 5797, 1027, 125, 12, 1;
...
From _Eric W. Weisstein_, Jun 11 2019: (Start)
a(2,1) = 1 since only P_2 has diameter 1.
a(3,1) = 1 since only C_3 has diameter 1.
a(3,2) = 1 since only P_3 has diameter 2.
a(4,1) = 1 since only K_4 has diameter 1.
a(4,2) = 4 since K_1,3, K4-e, the paw graph, and C_4 have diameter 2.
a(4,3) = 1 since only P_4 has diameter 3.
(End)
A241708
Number of simple connected graphs on n nodes with diameter 4.
Original entry on oeis.org
0, 0, 0, 0, 1, 8, 82, 1027, 19320, 598913
Offset: 1
A241709
Number of simple connected graphs on n nodes with diameter 5.
Original entry on oeis.org
0, 0, 0, 0, 0, 1, 9, 125, 1818, 37856
Offset: 1
A241710
Number of simple connected graphs on n nodes with diameter 6.
Original entry on oeis.org
0, 0, 0, 0, 0, 0, 1, 12, 180, 2928
Offset: 1
Showing 1-5 of 5 results.