A297989 Number of nX4 0..1 arrays with every element equal to 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

2, 49, 146, 466, 1446, 4648, 14888, 47399, 150849, 480015, 1528351, 4868127, 15504952, 49377480, 157242432, 500744003, 1594669951, 5078421202, 16172807093, 51503968299, 164019559229, 522337092408, 1663436972579, 5297389242128

Offset

1,1

Comments

Column 4 of A297993.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -6*a(n-2) +2*a(n-3) -5*a(n-4) +10*a(n-5) -19*a(n-6) -30*a(n-7) +29*a(n-8) +61*a(n-9) +81*a(n-10) -91*a(n-11) -78*a(n-12) -35*a(n-13) +86*a(n-14) +10*a(n-15) -35*a(n-16) -23*a(n-17) +16*a(n-18) +37*a(n-19) -32*a(n-20) +14*a(n-21) +6*a(n-22) -8*a(n-23) +4*a(n-24) for n>27

Example

Some solutions for n=7
..0..1..0..0. .0..1..0..0. .0..0..0..0. .0..1..0..0. .0..0..0..0
..0..1..0..0. .0..1..0..1. .1..1..1..1. .0..0..1..0. .1..1..1..0
..0..1..1..1. .1..1..0..1. .1..0..0..1. .1..1..1..0. .0..0..0..1
..1..0..0..0. .1..0..0..1. .0..1..0..1. .0..0..0..0. .0..1..1..0
..0..1..1..1. .0..1..1..1. .0..1..1..1. .0..1..1..1. .0..1..0..0
..1..0..0..0. .1..0..0..0. .0..1..0..1. .1..0..0..0. .0..1..0..1
..0..1..1..1. .1..1..1..1. .0..1..0..0. .1..1..1..1. .1..1..0..1

Crossrefs

Cf. A297993.

Sequence in context: A041287 A057563 A297819 * A028479 A189389 A001568

Adjacent sequences: A297986 A297987 A297988 * A297990 A297991 A297992

Keyword

nonn

Author

R. H. Hardin, Jan 10 2018

Status

approved