A281135 Number of nX4 0..2 arrays with no element equal to more than one of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

2, 112, 1046, 2368, 5368, 12064, 27218, 61508, 137320, 303016, 661750, 1436148, 3102354, 6664604, 14249996, 30349780, 64423304, 136341644, 287731246, 605682872, 1272111378, 2666358192, 5578178044, 11649555816, 24290213802

Offset

1,1

Comments

Column 4 of A281139.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-4) -19*a(n-6) -8*a(n-7) +4*a(n-8) +2*a(n-9) +5*a(n-10) +44*a(n-11) +14*a(n-12) -20*a(n-13) +3*a(n-14) +20*a(n-15) -40*a(n-16) -36*a(n-17) +16*a(n-18) +12*a(n-19) -16*a(n-20) +16*a(n-22) -4*a(n-24) for n>33

Example

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

Crossrefs

Cf. A281139.

Sequence in context: A231278 A117698 A274057 * A173214 A341782 A024341

Adjacent sequences: A281132 A281133 A281134 * A281136 A281137 A281138

Keyword

nonn

Author

R. H. Hardin, Jan 15 2017

Status

approved