OFFSET
3,6
COMMENTS
The number of edges is n+k-2.
Terms of this sequence can be computed using the tool "plantri". The expanded reference gives rows 3..15 of this table.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 3..171 (rows 3..15)
Gunnar Brinkmann and Brendan McKay, Fast generation of planar graphs (expanded edition), Tables 23-26.
FORMULA
T(n,2) = 1.
T(n,3) = A253186(n-2).
EXAMPLE
Triangle begins:
1;
1, 1, 1;
1, 2, 5, 2, 1;
1, 3, 17, 31, 22, 6, 2;
1, 4, 42, 157, 318, 265, 123, 26, 6;
1, 6, 87, 576, 2128, 4009, 4055, 2332, 804, 147, 17;
...
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Andrew Howroyd, Mar 27 2021
STATUS
approved