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A282372
Number of nX3 0..1 arrays with no 1 equal to more than four of its king-move neighbors, with the exception of exactly two elements.
1
0, 1, 20, 309, 3499, 33692, 309493, 2721044, 23193721, 193520569, 1587628975, 12850623027, 102883527733, 816204241881, 6425192293124, 50243446084946, 390619259367639, 3021431489931709, 23265194042723056, 178420043485112107
OFFSET
1,3
COMMENTS
Column 3 of A282377.
LINKS
FORMULA
Empirical: a(n) = 15*a(n-1) -42*a(n-2) -112*a(n-3) -540*a(n-4) +2619*a(n-5) +10088*a(n-6) +24930*a(n-7) -11745*a(n-8) -121823*a(n-9) -302973*a(n-10) -109557*a(n-11) +626061*a(n-12) +1677252*a(n-13) +1111167*a(n-14) -1607654*a(n-15) -4968711*a(n-16) -3987444*a(n-17) +1869096*a(n-18) +8096727*a(n-19) +7157916*a(n-20) -59475*a(n-21) -6680688*a(n-22) -6454986*a(n-23) -1842524*a(n-24) +1900140*a(n-25) +2314704*a(n-26) +1190024*a(n-27) +304272*a(n-28) +37152*a(n-29) +1728*a(n-30)
EXAMPLE
Some solutions for n=4
..1..1..0. .1..1..0. .0..0..1. .0..1..0. .0..0..0. .0..1..1. .0..1..1
..0..1..1. .1..1..1. .1..1..1. .1..1..0. .0..0..0. .1..1..0. .1..1..1
..0..1..1. .0..1..1. .1..1..1. .1..1..1. .1..1..1. .1..1..0. .0..1..0
..1..0..1. .1..0..0. .1..0..0. .1..0..1. .1..1..1. .0..1..1. .1..1..0
CROSSREFS
Cf. A282377.
Sequence in context: A016190 A016188 A006300 * A361293 A240799 A281931
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2017
STATUS
approved