A300430 Number of nX3 0..1 arrays with every element equal to 1, 2 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 6, 13, 33, 87, 228, 611, 1656, 4479, 12100, 32579, 87705, 236468, 638292, 1723867, 4656414, 12576659, 33964397, 91716558, 247664253, 668787690, 1806042197, 4877289821, 13171458556, 35570422970, 96059902903, 259414009161

Offset

1,2

Comments

Column 3 of A300435.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -19*a(n-2) +26*a(n-3) -20*a(n-4) +16*a(n-5) -21*a(n-6) +14*a(n-7) -6*a(n-8) +7*a(n-9) -25*a(n-10) +42*a(n-11) +42*a(n-12) -29*a(n-13) -71*a(n-14) -56*a(n-15) -15*a(n-16) +28*a(n-17) +78*a(n-18) +86*a(n-19) +54*a(n-20) -7*a(n-21) -26*a(n-22) -14*a(n-23) -5*a(n-24) -13*a(n-25) -11*a(n-26) +6*a(n-28) +4*a(n-29) -a(n-31)

Example

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

Crossrefs

Cf. A300435.

Sequence in context: A042607 A048693 A041068 * A300634 A301356 A037243

Adjacent sequences: A300427 A300428 A300429 * A300431 A300432 A300433

Keyword

nonn

Author

R. H. Hardin, Mar 05 2018

Status

approved