A251233 Number of (n+1) X (5+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.

2930, 5194, 9914, 20490, 44966, 103926, 250622, 626122, 1610186, 4240330, 11386550, 31076502, 85989998, 240797850, 681516362, 1947640474, 5616316454, 16333536118, 47886799742, 141482904522, 421114402730, 1262292036426

Offset

1,1

Comments

Column 5 of A251236.

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -63*a(n-2) +122*a(n-3) +13*a(n-4) -371*a(n-5) +317*a(n-6) +308*a(n-7) -370*a(n-8) -144*a(n-9) +128*a(n-10) +48*a(n-11).

Example

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

Crossrefs

Cf. A251236.

Sequence in context: A237079 A128149 A276671 * A251983 A251976 A251975

Adjacent sequences: A251230 A251231 A251232 * A251234 A251235 A251236

Keyword

nonn

Author

R. H. Hardin, Nov 30 2014

Status

approved