A237672 - OEIS

A237672

Number of (n+1) X (1+1) 0..3 arrays with the maximum plus the upper median plus the minimum of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one.

256, 1564, 9647, 63000, 412120, 2668500, 17280632, 112196812, 729345568, 4730716616, 30705881416, 199250972104, 1294118583944, 8396039853104, 54516655728608, 353723940339776, 2297049424994128, 14903574260972720

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OFFSET

1,1

COMMENTS

Column 1 of A237677.

LINKS

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

FORMULA

Empirical: a(n) = 1464*a(n-4) +21444*a(n-6) -217012*a(n-8) -5585804*a(n-10) -12617424*a(n-12) +351921344*a(n-14) +2542892384*a(n-16) +1019240768*a(n-18) -42797024832*a(n-20) -123435815936*a(n-22) +85546957824*a(n-24) +742456289792*a(n-26) +481891066880*a(n-28) -1227137187840*a(n-30) -1305858437120*a(n-32) +134355173376*a(n-34) +344315133952*a(n-36) -1108344832*a(n-38) -26916945920*a(n-40) -3468689408*a(n-42) -369098752*a(n-44) for n>45.

EXAMPLE

Some solutions for n=4

..2..2....0..0....2..2....2..0....3..2....0..2....2..3....2..2....0..2....3..1

..0..1....0..1....0..1....1..0....3..1....0..3....0..3....0..2....3..0....3..3

..2..0....1..0....0..2....0..3....2..2....1..3....2..1....0..3....1..3....2..0

..0..2....0..2....0..0....0..0....2..3....0..2....2..0....1..0....3..1....3..2

..3..1....2..0....2..1....3..1....3..3....1..2....3..0....0..2....3..0....3..0

CROSSREFS

Cf. A237677.

Sequence in context: A237403 A237399 A237677 * A237921 A237915 A238081

Adjacent sequences: A237669 A237670 A237671 * A237673 A237674 A237675

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 11 2014

STATUS

approved