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A318086
Number of nX3 0..1 arrays with every element unequal to 0, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
1, 2, 2, 7, 7, 11, 15, 62, 104, 141, 275, 741, 1325, 2194, 4346, 9703, 17959, 32463, 64123, 132534, 250208, 470401, 923631, 1843613, 3523413, 6742322, 13174390, 25884507, 49819771, 96089259, 187177999, 365170718, 705571836, 1365582829
OFFSET
1,2
COMMENTS
Column 3 of A318091.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -a(n-2) +2*a(n-3) +4*a(n-4) -12*a(n-5) +7*a(n-6) -12*a(n-7) +20*a(n-8) -6*a(n-9) +13*a(n-10) +10*a(n-11) -19*a(n-12) -2*a(n-13) -26*a(n-14) +26*a(n-15) -4*a(n-16) +10*a(n-17) -10*a(n-18) -2*a(n-19) -a(n-20) +a(n-22) +a(n-24)
EXAMPLE
All solutions for n=5
..0..1..0. .0..1..0. .0..0..0. .0..0..1. .0..1..0. .0..1..0. .0..1..0
..1..0..1. .1..1..0. .0..0..0. .0..1..0. .1..1..1. .1..0..1. .1..1..0
..0..0..1. .0..1..1. .0..0..0. .1..1..0. .0..0..0. .1..1..1. .0..1..1
..1..0..0. .0..1..0. .0..0..0. .0..1..1. .0..1..0. .0..0..0. .0..1..0
..1..0..1. .1..0..1. .0..0..0. .0..1..0. .1..0..1. .1..0..1. .1..0..0
CROSSREFS
Cf. A318091.
Sequence in context: A021443 A045923 A306238 * A244049 A271229 A199886
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 16 2018
STATUS
approved