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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. 1
2, 45, 164, 934, 4237, 21777, 105585, 523414, 2578424, 12726069, 62802085, 309849336, 1529212139, 7545987106, 37239443170, 183771070484, 906898467298, 4475474508545, 22086156194245, 108993766999235, 537877222587527 (list; graph; refs; listen; history; text; internal format)
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

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Last modified July 25 16:03 EDT 2021. Contains 346291 sequences. (Running on oeis4.)