A281601 Number of nX4 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

11, 110, 1283, 16198, 203276, 2563481, 32354824, 408458506, 5156857179, 65107404580, 822011501060, 10378295092963, 131031076361292, 1654331920396230, 20886756502623605, 263705605573971334

Offset

1,1

Comments

Column 4 of A281605.

Links

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

Formula

Empirical: a(n) = 13*a(n-1) +3*a(n-2) -87*a(n-3) -125*a(n-4) -116*a(n-5) +69*a(n-6) +522*a(n-7) -148*a(n-8) -199*a(n-9) +690*a(n-10) -105*a(n-11) -265*a(n-12) -155*a(n-13) -84*a(n-14) -23*a(n-15) -13*a(n-16) for n>18

Example

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

Crossrefs

Cf. A281605.

Sequence in context: A285541 A355407 A185535 * A266513 A356329 A055016

Adjacent sequences: A281598 A281599 A281600 * A281602 A281603 A281604

Keyword

nonn

Author

R. H. Hardin, Jan 25 2017

Status

approved