A303198 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

4, 6, 12, 23, 43, 105, 233, 479, 968, 2146, 4683, 9928, 20709, 44652, 96244, 205631, 435063, 930935, 1994977, 4266607, 9080728, 19396626, 41471567, 88657284, 189124509, 403873550, 862832200, 1843730503, 3936307111, 8406314159

Offset

1,1

Comments

Row 3 of A303197.

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-2) +12*a(n-4) -6*a(n-5) -7*a(n-6) -3*a(n-7) -26*a(n-8) +9*a(n-9) +14*a(n-10) +5*a(n-11) +18*a(n-12) -5*a(n-13) -9*a(n-14) -2*a(n-15) -3*a(n-16) +a(n-17) +a(n-18) for n>19

Example

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

Crossrefs

Cf. A303197.

Sequence in context: A098145 A307189 A054167 * A120211 A308471 A357809

Adjacent sequences: A303195 A303196 A303197 * A303199 A303200 A303201

Keyword

nonn

Author

R. H. Hardin, Apr 19 2018

Status

approved