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A298829
Number of nX3 0..1 arrays with every element equal to 1, 3, 4, 5 or 8 king-move adjacent elements, with upper left element zero.
1
0, 4, 1, 6, 10, 15, 60, 128, 267, 810, 1878, 4579, 12408, 30552, 77105, 200876, 505862, 1288511, 3311514, 8411436, 21467751, 54921524, 139947224, 357287611, 912689144, 2328342518, 5944207749, 15177139978, 38734201690, 98882999903, 252436571832
OFFSET
1,2
COMMENTS
Column 3 of A298834.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +3*a(n-2) +5*a(n-3) -22*a(n-4) -15*a(n-5) +17*a(n-6) +44*a(n-7) -13*a(n-8) -49*a(n-9) +74*a(n-10) +38*a(n-11) -91*a(n-12) -61*a(n-13) +42*a(n-14) +24*a(n-15) -4*a(n-16) +a(n-17) -a(n-18) -a(n-19) for n>20
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..1. .0..0..0. .0..1..0. .0..1..1. .0..0..0. .0..1..0
..0..0..1. .0..0..1. .0..0..0. .0..1..0. .0..1..1. .0..0..0. .0..1..0
..0..1..1. .1..1..1. .0..0..0. .1..1..1. .0..0..0. .1..1..1. .0..0..0
..0..0..1. .0..0..1. .1..1..1. .1..0..1. .0..1..1. .1..1..1. .1..0..1
..0..0..1. .0..0..1. .1..1..1. .1..0..1. .0..1..1. .1..1..1. .1..0..1
CROSSREFS
Cf. A298834.
Sequence in context: A333824 A083843 A094264 * A056140 A225419 A140895
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 27 2018
STATUS
approved