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A185605 Number of (n+1)X2 0..3 arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant 2
0, 580, 2366, 22236, 118616, 891506, 5489048, 38326452, 247830606, 1678338746, 11045857798, 73974786560, 490178170074, 3269292086024, 21718260697050, 144628225929208, 961688652955234, 6400460897406340, 42574178108712958 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 1 of A185609

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=10*a(n-1)-6*a(n-2)-197*a(n-3)+652*a(n-4)+68*a(n-5)-4460*a(n-6)+9172*a(n-7)-2564*a(n-8)-12176*a(n-9)+34398*a(n-10)-101637*a(n-11)+116495*a(n-12)+54653*a(n-13)-228940*a(n-14)+430952*a(n-15)-746674*a(n-16)+637912*a(n-17)+95538*a(n-18)-1125709*a(n-19)+2119961*a(n-20)-2867650*a(n-21)+2135142*a(n-22)+628180*a(n-23)-2741051*a(n-24)+3448532*a(n-25)-2105927*a(n-26)+61752*a(n-27)+756653*a(n-28)-607098*a(n-29)-875751*a(n-30)+882731*a(n-31)-276007*a(n-32)-379574*a(n-33)+211346*a(n-34)+16316*a(n-35)-52955*a(n-36)+8160*a(n-37)+2952*a(n-38)+864*a(n-39) for n>40

EXAMPLE

Some solutions for 3X2

..3..3....2..0....3..2....2..0....3..1....3..1....2..0....0..1....1..1....3..2

..0..0....2..0....3..2....0..0....3..2....0..0....0..0....0..2....0..0....3..1

..2..0....2..0....3..2....3..2....0..1....3..0....3..1....0..1....0..0....3..0

CROSSREFS

Sequence in context: A186786 A185609 A127694 * A186784 A185606 A206616

Adjacent sequences:  A185602 A185603 A185604 * A185606 A185607 A185608

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 31 2011

STATUS

approved

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Last modified October 16 20:36 EDT 2021. Contains 348047 sequences. (Running on oeis4.)