A300939 Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

3, 2, 5, 12, 19, 47, 101, 206, 411, 882, 1851, 3845, 7965, 16694, 34883, 72716, 151521, 316419, 660399, 1377674, 2873815, 5997158, 12513837, 26109233, 54474709, 113665030, 237165643, 494844028, 1032487175, 2154302515, 4494977409

Offset

1,1

Comments

Column 3 of A300944.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) -5*a(n-3) -2*a(n-4) -3*a(n-5) -a(n-6) +22*a(n-7) +7*a(n-8) -33*a(n-9) -28*a(n-10) +11*a(n-11) +50*a(n-12) +40*a(n-13) -50*a(n-14) -82*a(n-15) +3*a(n-16) +96*a(n-17) +79*a(n-18) -49*a(n-19) -85*a(n-20) -9*a(n-21) +46*a(n-22) +55*a(n-23) +17*a(n-24) -28*a(n-25) -31*a(n-26) -11*a(n-27) +a(n-28) +5*a(n-29) +4*a(n-30) +a(n-31) for n>32

Example

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

Crossrefs

Cf. A300944.

Sequence in context: A130597 A075146 A353403 * A062941 A211018 A374428

Adjacent sequences: A300936 A300937 A300938 * A300940 A300941 A300942

Keyword

nonn

Author

R. H. Hardin, Mar 16 2018

Status

approved