OFFSET
1,19
LINKS
Hugo Pfoertner, Table of n, a(n) for n = 1..325 (rows 1..25, first 18 rows extracted from Robinson's tables, rows 19-20 from Andrew Howroyd)
R. W. Robinson, Tables of 2-Connected and 3-Connected Graphs by Nodes and Edges, Table IV, pages 4-9.
FORMULA
T(n, n) = 1 for n >= 3.
T(n, n-1) = A253186(n-3) for n >= 3.
EXAMPLE
Triangle T(n,k) begins (n edges >= 1, k vertices >= 2):
1;
0, 0;
0, 1, 0;
0, 0, 1, 0;
0, 0, 1, 1, 0;
0, 0, 1, 2, 1, 0;
0, 0, 0, 3, 3, 1, 0;
0, 0, 0, 2, 9, 4, 1, 0;
0, 0, 0, 1, 14, 20, 6, 1, 0;
0, 0, 0, 1, 12, 50, 40, 7, 1, 0;
0, 0, 0, 0, 8, 82, 161, 70, 9, 1, 0;
0, 0, 0, 0, 5, 94, 429, 433, 121, 11, 1, 0;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Nov 23 2020
EXTENSIONS
First row and column removed by Andrew Howroyd, Dec 05 2020
STATUS
approved