|
| |
|
|
A341918
|
|
Number of strong triangulations of a fixed hexagon with n interior nodes.
|
|
3
|
|
|
|
1, 15, 155, 1410, 12165, 102548, 856205, 7128420, 59386655, 495973610, 4156326090, 34965061950, 295326872685, 2504471904060, 21322339850120, 182220932483936, 1562911922345700, 13451387178653575, 116149864521206475, 1006036370555080950, 8739349976276626707, 76128234963921173340
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
|
|
|
FORMULA
|
a(n) = 120*(67*n^2 + 138*n + 68)*(4*n+7)!/((3*n+12)!*(n-1)!).
|
|
|
PROG
|
(PARI) a(n) = {120*(67*n^2 + 138*n + 68)*(4*n+7)!/((3*n+12)!*(n-1)!)}
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
