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A194890
Number of lower triangles of an n X n 0..5 array with new values introduced in row major order 0..5 and no two horizontal or vertical neighbors of any element equal
0
1, 3, 34, 3936, 1797696, 2054111040, 5741390328960, 39210440893622016
OFFSET
1,2
COMMENTS
Column 5 of A194893
EXAMPLE
Some solutions for 4X4
..0........0........0........0........0........0........0........0
..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2
..1.3.4....3.4.1....1.3.4....3.2.1....3.3.4....3.2.1....3.0.1....3.3.4
..0.0.4.1..5.5.2.0..2.3.5.2..0.0.1.2..0.1.1.0..3.4.5.0..3.4.4.3..2.1.0.5
CROSSREFS
Sequence in context: A366137 A337069 A102104 * A197434 A194891 A194892
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 04 2011
STATUS
approved