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A187433 Number of (n+1)X2 0..2 arrays with no 2X2 subblock commuting with any of its horizontal and vertical 2X2 subblock neighbors 1
81, 646, 5344, 44195, 365485, 3022484, 24995294, 206705746, 1709412335, 14136474668, 116905624191, 966784526492, 7995101408646, 66117779901555, 546779908805283, 4521752985630622, 37393930782377369, 309239815576130829 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A187441

LINKS

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

FORMULA

Empirical: a(n)=a(n-1)+32*a(n-2)+160*a(n-3)+468*a(n-4)+929*a(n-5)+1244*a(n-6)+881*a(n-7)-471*a(n-8)-2281*a(n-9)-3120*a(n-10)-1743*a(n-11)+1386*a(n-12)+3903*a(n-13)+3547*a(n-14)+613*a(n-15)-2124*a(n-16)-2314*a(n-17)-511*a(n-18)+932*a(n-19)+840*a(n-20)+73*a(n-21)-281*a(n-22)-172*a(n-23)-25*a(n-24)+8*a(n-25)+2*a(n-26) for n>27

EXAMPLE

Some solutions for 3X2

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

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

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

CROSSREFS

Sequence in context: A237629 A236720 A187441 * A269055 A236876 A185366

Adjacent sequences:  A187430 A187431 A187432 * A187434 A187435 A187436

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 10 2011

STATUS

approved

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Last modified June 24 06:17 EDT 2021. Contains 345416 sequences. (Running on oeis4.)