A237135 Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the upper median of every 2X2 subblock equal

256, 1500, 8414, 52484, 328768, 2145192, 14152560, 95414944, 649185798, 4478130100, 31091450584, 217843944144, 1532986230904, 10852686898168, 77047991907070, 549127517842812, 3920693547270496, 28062818940398024

Offset

1,1

Comments

Column 1 of A237142

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -1186*a(n-3) +4300*a(n-4) +29836*a(n-5) -178043*a(n-6) -268628*a(n-7) +3127196*a(n-8) -779130*a(n-9) -28579040*a(n-10) +32590712*a(n-11) +142648608*a(n-12) -254087072*a(n-13) -375342992*a(n-14) +955527424*a(n-15) +408264640*a(n-16) -1902301152*a(n-17) +178371840*a(n-18) +1899365760*a(n-19) -742376448*a(n-20) -734054400*a(n-21) +418037760*a(n-22)

Example

Some solutions for n=4
..2..3....3..1....1..3....0..0....0..2....3..1....0..2....2..3....0..2....1..3
..3..3....3..0....3..1....1..3....1..2....0..3....3..3....2..2....3..0....0..2
..3..0....3..0....3..3....1..1....2..1....3..1....0..1....3..1....2..2....2..3
..3..3....0..3....3..3....1..3....1..2....3..1....3..3....1..2....0..3....2..1
..0..3....3..1....2..3....1..0....2..0....3..1....1..2....3..1....1..2....3..2

Crossrefs

Sequence in context: A237974 A237967 A237142 * A197709 A198073 A197907

Adjacent sequences: A237132 A237133 A237134 * A237136 A237137 A237138

Keyword

nonn

Author

R. H. Hardin, Feb 04 2014

Status

approved