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

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