A233127 - OEIS

A233127

Number of nX6 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs)

136, 124928, 127533056, 132682612736, 138791062863872, 145451790488305664, 152534173898504142848, 160000135886807521820672, 167846256915736431983329280, 176082743571854371127073701888

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OFFSET

1,1

COMMENTS

Column 6 of A233129

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 1984*a(n-1) -1314816*a(n-2) +411303936*a(n-3) -70111985664*a(n-4) +6893422510080*a(n-5) -389708152569856*a(n-6) +11733988091625472*a(n-7) -145241087982698496*a(n-8)

EXAMPLE

Some solutions for n=2

..0..1..2..4..2..0....0..1..2..5..1..5....0..1..0..1..5..2....0..1..0..4..2..1

..1..5..4..2..0..4....4..2..4..3..5..2....3..5..4..0..4..5....1..5..4..2..4..2

CROSSREFS

Sequence in context: A278185 A225832 A233172 * A157880 A233254 A001330

Adjacent sequences: A233124 A233125 A233126 * A233128 A233129 A233130

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 04 2013

STATUS

approved