A302220 Number of nX4 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

2, 45, 164, 934, 4237, 21777, 105585, 523414, 2578424, 12726069, 62802085, 309849336, 1529212139, 7545987106, 37239443170, 183771070484, 906898467298, 4475474508545, 22086156194245, 108993766999235, 537877222587527

Offset

1,1

Comments

Column 4 of A302224.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +11*a(n-2) -42*a(n-3) -95*a(n-4) +21*a(n-5) +327*a(n-6) +1255*a(n-7) +317*a(n-8) -5188*a(n-9) -6921*a(n-10) +6005*a(n-11) +22780*a(n-12) +10157*a(n-13) -27962*a(n-14) -42374*a(n-15) -2355*a(n-16) +48767*a(n-17) +45664*a(n-18) -6331*a(n-19) -46138*a(n-20) -32422*a(n-21) +6577*a(n-22) +23809*a(n-23) +15150*a(n-24) -2372*a(n-25) -6308*a(n-26) -2794*a(n-27) -68*a(n-28) +832*a(n-29) +20*a(n-30) for n>34

Example

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

Crossrefs

Cf. A302224.

Sequence in context: A316637 A281661 A019579 * A302666 A304693 A200158

Adjacent sequences: A302217 A302218 A302219 * A302221 A302222 A302223

Keyword

nonn

Author

R. H. Hardin, Apr 03 2018

Status

approved