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A317769
Number of nX4 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
5, 7, 11, 10, 14, 23, 32, 55, 86, 143, 226, 367, 599, 967, 1581, 2574, 4220, 6868, 11207, 18264, 29787, 48612, 79373, 129646, 211599, 345398, 563683, 919995, 1501558, 2451270, 4001959, 6533101, 10664515, 17407925, 28415437, 46383330, 75715684
OFFSET
1,1
COMMENTS
Column 4 of A317773.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-4) +6*a(n-7) -a(n-8) -a(n-9) -a(n-10) -7*a(n-11) -7*a(n-12) +2*a(n-13) -a(n-14) for n>23
EXAMPLE
Some solutions for n=5
..0..0..0..0. .0..0..0..1. .0..1..1..1. .0..0..0..1. .0..0..0..1
..0..0..0..0. .0..0..0..0. .0..0..1..1. .0..0..0..0. .0..0..0..0
..0..0..0..0. .0..0..0..0. .0..0..0..1. .0..0..0..0. .0..0..0..0
..1..0..0..0. .0..0..0..0. .0..0..0..0. .1..0..0..0. .0..0..0..0
..1..1..0..0. .1..0..0..0. .0..0..0..0. .1..1..0..0. .0..0..0..0
CROSSREFS
Cf. A317773.
Sequence in context: A357099 A277777 A254930 * A104200 A249916 A115044
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 06 2018
STATUS
approved