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A233199
Number of nX5 0..7 arrays with no element x(i,j) adjacent to itself or value 7-x(i,j) horizontally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 4 5 and 6, 2 appearing before 3 4 and 5, and 3 appearing before 4 in row major order (unlabelled 8-colorings with no clashing color pairs)
1
48, 8256, 2779136, 981532672, 352524959744, 127365174788096, 46111939268444160, 16706602064729341952, 6054323596680792899584, 2194196637563524913037312, 795235812066308877870694400
OFFSET
1,1
COMMENTS
Column 5 of A233202
LINKS
FORMULA
Empirical: a(n) = 736*a(n-1) -203776*a(n-2) +33062912*a(n-3) -3665821696*a(n-4) +270851375104*a(n-5) -10685878632448*a(n-6) -116548232544256*a(n-7) +35184372088832000*a(n-8) -1423137482249076736*a(n-9) +18446744073709551616*a(n-10) for n>11
EXAMPLE
Some solutions for n=2
..0..1..2..3..0....0..1..2..1..3....0..1..2..3..5....0..1..2..0..3
..5..3..0..5..4....4..0..3..0..1....3..7..1..0..1....4..0..3..6..2
CROSSREFS
Sequence in context: A299943 A226257 A293094 * A232160 A260212 A295590
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 05 2013
STATUS
approved