A302151 Number of 3Xn 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.

4, 1, 4, 5, 11, 34, 88, 271, 798, 2368, 7071, 21110, 63163, 188980, 565622, 1693239, 5069374, 15178832, 45451143, 136102762, 407567006, 1220499079, 3654940301, 10945255479, 32777313021, 98157159720, 293948595170, 880280943171

Offset

1,1

Comments

Row 3 of A302150.

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) +6*a(n-3) -10*a(n-4) +11*a(n-5) -24*a(n-6) +11*a(n-7) -45*a(n-8) +22*a(n-9) -38*a(n-10) +39*a(n-11) -21*a(n-12) +68*a(n-13) +28*a(n-14) +73*a(n-15) -25*a(n-16) -16*a(n-17) -37*a(n-18) -11*a(n-19) -11*a(n-20) -16*a(n-21) -7*a(n-22) +3*a(n-24) +a(n-25) for n>27

Example

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

Crossrefs

Cf. A302150.

Sequence in context: A286327 A081773 A324836 * A167431 A205848 A297701

Adjacent sequences: A302148 A302149 A302150 * A302152 A302153 A302154

Keyword

nonn

Author

R. H. Hardin, Apr 02 2018

Status

approved