OFFSET
0,3
COMMENTS
LINKS
Indranil Ghosh, Table of n, a(n) for n = 0..447
Michael Wallner, A bijection of plane increasing trees with relaxed binary trees of right height at most one, arXiv:1706.07163 [math.CO], 2017, Table 2 on p. 13.
FORMULA
EXAMPLE
a(2)= 3*9-24=3, a(3)= 3*44-120=12, a(4)= 3*265-720=75, ...
MAPLE
seq(3*floor(((n+2)!+1)/E) - (n+2)!, n=1..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary Detlefs, Apr 16 2010
EXTENSIONS
Data section corrected by Indranil Ghosh, Feb 15 2017
STATUS
approved