A301660 Number of nX6 0..1 arrays with every element equal to 0, 1 or 4 horizontally or vertically adjacent elements, with upper left element zero.

13, 14, 26, 45, 99, 254, 696, 2013, 5953, 17878, 54126, 164525, 501455, 1530694, 4676360, 14293737, 43703389, 133647942, 408746766, 1250182369, 3823920719, 11696450282, 35777089740, 109435800649, 334746407201, 1023938030574

Offset

1,1

Comments

Column 6 of A301662.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -2*a(n-2) +2*a(n-3) -14*a(n-4) -7*a(n-5) +3*a(n-6) +44*a(n-7) +22*a(n-8) -28*a(n-9) -45*a(n-10) -15*a(n-11) +25*a(n-12) +22*a(n-13) +2*a(n-14) -11*a(n-15) -4*a(n-16) +a(n-17) +2*a(n-18)

Example

Some solutions for n=5
..0..1..0..1..0..1. .0..1..0..1..0..1. .0..1..0..1..0..1. .0..1..0..1..0..1
..0..1..0..1..0..1. .1..1..1..0..1..0. .1..0..1..1..1..0. .1..0..1..1..1..0
..1..0..1..0..1..0. .0..1..0..1..0..1. .0..1..0..1..0..1. .0..1..0..1..0..1
..0..1..0..1..1..1. .1..0..0..0..1..0. .1..1..1..0..1..0. .1..0..0..0..1..0
..1..0..1..0..1..0. .0..1..0..1..0..1. .0..1..0..1..0..1. .0..1..0..1..0..1

Crossrefs

Cf. A301662.

Sequence in context: A079831 A022803 A112653 * A022103 A224224 A041342

Adjacent sequences: A301657 A301658 A301659 * A301661 A301662 A301663

Keyword

nonn

Author

R. H. Hardin, Mar 25 2018

Status

approved