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R. H. Hardin, <a href="/A282476/b282476.txt">Table of n, a(n) for n = 1..210</a>
allocated for R. H. Hardin
Number of nX3 0..1 arrays with no 1 equal to more than three of its king-move neighbors, with the exception of exactly two elements.
0, 5, 40, 483, 4328, 36425, 297210, 2327123, 17768964, 132986406, 978703597, 7105001436, 50987747977, 362304776490, 2552515814181, 17848926362232, 123989575656587, 856256223208439, 5882111754640392, 40216030450523925
1,2
Column 3 of A282481.
Empirical: a(n) = 15*a(n-1) -60*a(n-2) +38*a(n-3) -417*a(n-4) +2211*a(n-5) +254*a(n-6) +9714*a(n-7) -19866*a(n-8) +11292*a(n-9) -83508*a(n-10) +94758*a(n-11) -162290*a(n-12) +333372*a(n-13) -354804*a(n-14) +698218*a(n-15) -723297*a(n-16) +960537*a(n-17) -1190332*a(n-18) +1011360*a(n-19) -1264665*a(n-20) +756661*a(n-21) -868110*a(n-22) +386904*a(n-23) -278456*a(n-24) +47328*a(n-25) -2976*a(n-26) +64*a(n-27)
Some solutions for n=4
..0..0..1. .1..0..0. .1..1..0. .1..0..0. .1..1..0. .1..0..1. .1..0..1
..1..1..0. .0..1..1. .1..1..1. .1..1..0. .1..0..0. .0..1..0. .1..1..0
..0..1..1. .1..1..0. .0..0..0. .0..1..1. .1..1..1. .1..1..0. .0..1..0
..0..0..1. .1..0..1. .0..1..0. .0..0..1. .1..0..0. .1..0..1. .0..1..1
Cf. A282481.
allocated
nonn
R. H. Hardin, Feb 16 2017
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editing
allocated for R. H. Hardin
allocated
approved