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R. H. Hardin, <a href="/A298225/b298225.txt">Table of n, a(n) for n = 1..210</a>
allocated for R. H. Hardin
Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 king-move adjacent elements, with upper left element zero.
3, 4, 5, 17, 12, 100, 219, 498, 1999, 4953, 13928, 45164, 120865, 355474, 1065723, 2987665, 8792232, 25703174, 73648001, 215508142, 625811209, 1809121989, 5271819208, 15292192284, 44347119815, 128947618162, 374125557341
1,1
Column 3 of A298230.
Empirical: a(n) = a(n-1) +4*a(n-2) +13*a(n-3) -14*a(n-4) -29*a(n-5) -23*a(n-6) +29*a(n-7) +56*a(n-8) -30*a(n-9) -7*a(n-10) +41*a(n-11) +2*a(n-12) -26*a(n-13) -12*a(n-14) -15*a(n-15) -7*a(n-16) +16*a(n-17) +2*a(n-18) for n>19
Some solutions for n=7
..0..1..1. .0..1..0. .0..1..0. .0..0..1. .0..0..1. .0..1..0. .0..0..1
..0..1..1. .0..1..0. .0..1..0. .0..0..1. .0..0..0. .0..1..0. .0..0..1
..1..1..0. .1..1..1. .0..0..0. .1..1..1. .1..0..1. .0..0..0. .1..1..1
..1..1..0. .0..1..0. .1..0..1. .1..1..0. .0..0..1. .1..0..1. .1..1..0
..1..0..0. .1..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0. .0..0..1
..1..1..0. .0..1..1. .1..1..1. .1..1..1. .0..0..1. .1..1..1. .0..0..0
..1..1..0. .0..1..1. .1..1..0. .1..1..0. .0..0..1. .0..1..1. .1..0..1
Cf. A298230.
allocated
nonn
R. H. Hardin, Jan 15 2018
approved
editing
allocated for R. H. Hardin
allocated
approved