A236654 Number of (n+1)X(1+1) 0..3 arrays colored with the sum of the upper and lower median values of each 2X2 subblock

256, 2896, 32424, 370352, 4235056, 48229536, 549313480, 6261494544, 71367397200, 813298398848, 9268602995176, 105631275036528, 1203833778123600, 13719487336424928, 156354509776304744, 1781900315719572176

Offset

1,1

Comments

Column 1 of A236657

Links

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

Formula

Empirical: a(n) = 32*a(n-2) +510*a(n-3) +4422*a(n-4) +20562*a(n-5) +76184*a(n-6) +152730*a(n-7) -90401*a(n-8) -1395282*a(n-9) -5373988*a(n-10) -8188928*a(n-11) +9036688*a(n-12) +47478176*a(n-13) +64503872*a(n-14) +4474624*a(n-15) -119940096*a(n-16) -162693120*a(n-17) -71368704*a(n-18)

Example

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

Crossrefs

Sequence in context: A235582 A236657 A235579 * A236198 A236195 A236592

Adjacent sequences: A236651 A236652 A236653 * A236655 A236656 A236657

Keyword

nonn

Author

R. H. Hardin, Jan 29 2014

Status

approved