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A205515 Number of (n+1)X4 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock differing from each horizontal or vertical neighbor 1
1683, 17166, 205803, 2343348, 27630789, 312856410, 3703472454, 41913844878, 495981580533, 5614380251520, 66435526164984, 752013955358760, 8898757611781614, 100729081045683252, 1191949103431492563 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A205520

LINKS

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

FORMULA

Empirical: a(n) = 109*a(n-2) +2908*a(n-4) +57127*a(n-6) +121246*a(n-8) +256071*a(n-10) -166046*a(n-12) +879719*a(n-14) -1582201*a(n-16) +1663127*a(n-18) +1566104*a(n-20) -827026*a(n-22) -212087*a(n-24) +1333439*a(n-26) -568096*a(n-28) -811927*a(n-30) +48232*a(n-32) +136964*a(n-34) +17464*a(n-36) -428*a(n-38) +32*a(n-40) for n>41

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A205739 A031719 A206671 * A335338 A263061 A281062

Adjacent sequences: A205512 A205513 A205514 * A205516 A205517 A205518

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 28 2012

STATUS

approved

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Last modified February 6 23:12 EST 2023. Contains 360111 sequences. (Running on oeis4.)