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A186490 T(n,k)=Number of (n+1)X(k+1) 0..7 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors 2
4096, 1709, 1709, 33182, 4834, 33182, 23215, 9789, 9789, 23215, 275175, 49867, 269126, 49867, 275175, 217601, 91096, 144828, 144828, 91096, 217601, 2199713, 383152, 2196353, 1024481, 2196353, 383152, 2199713, 1960451, 740408, 1359050 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....4096.....1709.....33182.....23215.....275175.....217601.....2199713

.....1709.....4834......9789.....49867......91096.....383152......740408

....33182.....9789....269126....144828....2196353....1359050....17630852

....23215....49867....144828...1024481....1510299....8146732....11226859

...275175....91096...2196353...1510299...21122896...11602073...169362234

...217601...383152...1359050...8146732...11602073...70300633....84490329

..2199713...740408..17630852..11226859..169362234...84490329..1381305433

..1960451..3134584..12757534..66448348..106808569..574957529...742720601

.17761659..6273818.142040510..97175595.1363387642..722990905.11158847769

.17610501.25715484.117448824.541063232.1001273881.4662288121..7072233273

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..840

FORMULA

Empirical, for every column: a(n)=2*a(n-1)+6*a(n-2)-14*a(n-3)+14*a(n-4)-7*a(n-5) for n>k+13

EXAMPLE

Some solutions for 4X3

..0..5..0....2..6..0....0..0..0....5..0..3....5..1..0....0..0..7....3..1..0

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

..0..5..0....0..4..0....4..0..0....1..0..5....0..2..0....7..0..0....0..0..0

..5..0..5....1..0..4....0..4..1....0..1..0....3..0..2....0..7..4....2..0..0

CROSSREFS

Sequence in context: A182686 A176768 A223601 * A223694 A186489 A221261

Adjacent sequences:  A186487 A186488 A186489 * A186491 A186492 A186493

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Feb 22 2011

STATUS

approved

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Last modified August 14 07:04 EDT 2020. Contains 336477 sequences. (Running on oeis4.)