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A301840
Number of nX7 0..1 arrays with every element equal to 0, 1 or 2 horizontally or antidiagonally adjacent elements, with upper left element zero.
1
64, 2778, 72514, 1986213, 54948498, 1518341751, 41966406867, 1159968653556, 32062561937804, 886245421510973, 24496909108346419, 677125561489883191, 18716618615716379268, 517351460289528901541, 14300262505893118372023
OFFSET
1,1
COMMENTS
Column 7 of A301841.
FORMULA
Empirical recurrence of order 53 (see link above)
EXAMPLE
Some solutions for n=5
..0..0..1..0..0..1..0. .0..0..1..0..0..1..0. .0..0..1..0..0..1..1
..0..0..1..0..1..1..0. .0..0..1..0..0..1..1. .0..0..1..0..0..0..1
..0..0..1..0..0..1..0. .0..0..1..0..1..0..0. .0..0..1..1..1..1..0
..0..1..0..0..1..1..0. .1..0..0..1..0..1..1. .1..1..0..0..0..1..1
..0..1..1..0..1..0..1. .1..1..0..1..0..1..1. .0..1..1..0..0..0..0
CROSSREFS
Cf. A301841.
Sequence in context: A284228 A017319 A036531 * A302068 A281475 A302628
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 27 2018
STATUS
approved