login
A270110
Number of n X n 0..7 arrays with some element plus some horizontally or vertically adjacent neighbor totalling seven exactly once.
0
0, 1344, 45440640, 38799000374400, 1043364062813432764992, 953623090124975369688224358912, 30710864722727618437291310619830386096704
OFFSET
1,2
COMMENTS
Diagonal of A270118.
EXAMPLE
Some solutions for n=2
..5..2. .0..2. .0..0. .7..3. .5..1. .5..2. .4..5. .2..1. .7..5. .0..6
..5..1. .6..5. .7..5. .4..3. .2..7. .3..1. .0..2. .5..0. .0..3. .7..7
CROSSREFS
Cf. A270118.
Sequence in context: A230974 A239192 A172686 * A224566 A053770 A094037
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 11 2016
STATUS
approved