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A235233 Number of (n+1)X(2+1) 0..6 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant stress tilted 1X1 tilings) 1
420, 1288, 3688, 11728, 34916, 113940, 348876, 1158552, 3626376, 12193672, 38853396, 131871756, 426383532, 1457769280, 4770857720, 16406943392, 54238894212, 187427003188, 624847358508, 2167920197880, 7278838832680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A235239

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) +47*a(n-2) -331*a(n-3) -846*a(n-4) +7735*a(n-5) +6531*a(n-6) -99876*a(n-7) -4062*a(n-8) +780931*a(n-9) -294777*a(n-10) -3829232*a(n-11) +2187642*a(n-12) +11922251*a(n-13) -7106223*a(n-14) -23840076*a(n-15) +11482195*a(n-16) +31200479*a(n-17) -9197246*a(n-18) -26295345*a(n-19) +2967600*a(n-20) +13895070*a(n-21) +468804*a(n-22) -4403844*a(n-23) -634896*a(n-24) +759672*a(n-25) +171504*a(n-26) -54432*a(n-27) -15552*a(n-28)

EXAMPLE

Some solutions for n=4

..3..5..4....0..2..0....3..2..6....4..2..5....3..0..3....4..6..4....5..3..4

..5..1..6....4..0..4....0..5..3....0..4..1....2..5..2....5..1..5....2..6..1

..2..4..3....3..5..3....2..1..5....5..3..6....5..2..5....4..6..4....5..3..4

..5..1..6....6..2..6....1..6..4....0..4..1....0..3..0....6..2..6....1..5..0

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

CROSSREFS

Sequence in context: A135196 A259025 A281210 * A251084 A250383 A145678

Adjacent sequences:  A235230 A235231 A235232 * A235234 A235235 A235236

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 05 2014

STATUS

approved

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Last modified June 18 18:17 EDT 2021. Contains 345120 sequences. (Running on oeis4.)