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A237456 Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the lower median of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one. 1
81, 308, 1144, 4272, 16280, 61152, 231680, 869120, 3299584, 12382208, 46966784, 176229376, 668720640, 2509305856, 9520095232, 35722403840, 135538946048, 508589948928, 1929634152448, 7240635777024, 27472062906368, 103084621299712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 136*a(n-4) + 832*a(n-6) + 1600*a(n-8) + 1024*a(n-10).

Empirical g.f.: x*(81 + 308*x + 1144*x^2 + 4272*x^3 + 5264*x^4 + 19264*x^5 + 8704*x^6 + 31872*x^7 + 4096*x^8 + 18432*x^9) / (1 - 136*x^4 - 832*x^6 - 1600*x^8 - 1024*x^10). - Colin Barker, Oct 22 2018

EXAMPLE

Some solutions for n=5:

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

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

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

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

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

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

CROSSREFS

Column 1 of A237463.

Sequence in context: A236011 A206678 A237463 * A183994 A237703 A237696

Adjacent sequences:  A237453 A237454 A237455 * A237457 A237458 A237459

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 08 2014

STATUS

approved

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Last modified August 11 03:41 EDT 2022. Contains 356046 sequences. (Running on oeis4.)