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A301612
Number of nX5 0..1 arrays with every element equal to 1, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.
1
3, 111, 2131, 40085, 758338, 14345706, 271301458, 5131197358, 97045266159, 1835413254015, 34712996298775, 656524254453280, 12416789603607923, 234837748693978527, 4441467446525879000, 84001117092821240904
OFFSET
1,1
COMMENTS
Column 5 of A301615.
FORMULA
Empirical recurrence of order 68 (see link above)
EXAMPLE
Some solutions for n=5
..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0
..1..1..1..0..0. .0..0..1..0..1. .1..0..1..1..0. .1..1..1..1..0
..1..1..1..1..0. .1..0..1..0..1. .1..1..1..0..1. .1..1..0..0..0
..0..0..0..1..1. .1..0..1..1..1. .1..1..0..0..1. .0..1..1..0..0
..1..1..1..1..1. .1..0..1..1..1. .1..1..0..0..1. .0..1..1..1..1
CROSSREFS
Cf. A301615.
Sequence in context: A243464 A114738 A111091 * A180765 A232769 A066138
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 24 2018
STATUS
approved