A302213 Number of 3Xn 0..1 arrays with every element equal to 0, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

4, 2, 16, 5, 32, 22, 72, 101, 216, 486, 968, 2541, 5598, 14718, 35506, 91947, 231984, 597758, 1533828, 3954067, 10201602, 26336704, 68062810, 175893407, 454813604, 1176002162, 3041473404, 7866219629, 20346282584, 52627527962, 136129978706

Offset

1,1

Comments

Row 3 of A302212.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +4*a(n-2) -29*a(n-3) -3*a(n-4) +96*a(n-5) -14*a(n-6) -187*a(n-7) +39*a(n-8) +246*a(n-9) -52*a(n-10) -230*a(n-11) +48*a(n-12) +146*a(n-13) -29*a(n-14) -57*a(n-15) +9*a(n-16) +12*a(n-17) -a(n-18) -a(n-19) for n>20

Example

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

Crossrefs

Cf. A302212.

Sequence in context: A285362 A109922 A090640 * A090881 A191452 A348685

Adjacent sequences: A302210 A302211 A302212 * A302214 A302215 A302216

Keyword

nonn

Author

R. H. Hardin, Apr 03 2018

Status

approved