A317769 Number of nX4 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

5, 7, 11, 10, 14, 23, 32, 55, 86, 143, 226, 367, 599, 967, 1581, 2574, 4220, 6868, 11207, 18264, 29787, 48612, 79373, 129646, 211599, 345398, 563683, 919995, 1501558, 2451270, 4001959, 6533101, 10664515, 17407925, 28415437, 46383330, 75715684

Offset

1,1

Comments

Column 4 of A317773.

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-4) +6*a(n-7) -a(n-8) -a(n-9) -a(n-10) -7*a(n-11) -7*a(n-12) +2*a(n-13) -a(n-14) for n>23

Example

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

Crossrefs

Cf. A317773.

Sequence in context: A357099 A277777 A254930 * A104200 A249916 A115044

Adjacent sequences: A317766 A317767 A317768 * A317770 A317771 A317772

Keyword

nonn

Author

R. H. Hardin, Aug 06 2018

Status

approved