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A236730 Number of (n+1)X(1+1) 0..2 arrays with the upper median minus the lower median of every 2X2 subblock equal 1
81, 345, 1497, 6663, 29617, 132471, 592001, 2651151, 11872153, 53217175, 238621713, 1070656959, 4805940169, 21584396967, 96984517953, 435991819343, 1960896534009, 8823336533943, 39719697816561, 178884059892959 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A236737

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -9*a(n-2) -109*a(n-3) +254*a(n-4) +260*a(n-5) -1156*a(n-6) +576*a(n-7) +944*a(n-8) -1024*a(n-9) +256*a(n-10)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

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

CROSSREFS

Sequence in context: A237242 A236089 A236737 * A237324 A237730 A237317

Adjacent sequences:  A236727 A236728 A236729 * A236731 A236732 A236733

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 30 2014

STATUS

approved

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Last modified September 21 04:58 EDT 2020. Contains 337267 sequences. (Running on oeis4.)