VOOZH about

URL: https://oeis.org/A153987

⇱ A153987 - OEIS

login
A153987
Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with every one adjacent to exactly 2 other ones.
0
1, 1, 2, 3, 5, 12, 33, 97, 381, 1490, 7757, 42774, 307960, 2294754, 22718581, 231171797, 3121763126, 43651298703, 807916379400, 15440457456928, 391605380566734, 10243338678890245, 355535039683009851
OFFSET
0,3
CROSSREFS
Sequence in context: A284910 A233231 A319912 * A228905 A369847 A306038
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 04 2009
STATUS
approved