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A295047
Number of nX4 0..1 arrays with each 1 horizontally or vertically adjacent to 0 or 2 1s.
1
8, 48, 270, 1569, 9045, 52199, 301306, 1739181, 10038808, 57945607, 334471955, 1930628323, 11143914889, 64324570123, 371292350727, 2143162565884, 12370698651477, 71405775600211, 412166275575168, 2379093810054735
OFFSET
1,1
COMMENTS
Column 4 of A295051.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +6*a(n-2) -4*a(n-3) -25*a(n-4) -13*a(n-5) -31*a(n-6) -19*a(n-7) -56*a(n-8) +83*a(n-9) +39*a(n-10) +23*a(n-11) +53*a(n-12) +14*a(n-13) +15*a(n-14) +2*a(n-15) -4*a(n-16) -a(n-17) -a(n-18)
EXAMPLE
Some solutions for n=6
..1..0..0..0. .0..0..0..0. .1..0..0..0. .1..1..0..0. .0..1..0..1
..0..1..0..0. .1..0..0..1. .0..0..1..0. .1..1..0..1. .0..0..1..0
..0..0..0..0. .0..0..0..0. .0..1..0..1. .0..0..0..0. .0..1..0..1
..0..0..0..1. .1..0..0..0. .0..0..0..0. .0..1..0..1. .1..0..1..0
..0..1..0..0. .0..1..0..0. .1..1..0..0. .0..0..0..0. .0..1..0..1
..0..0..1..0. .0..0..0..0. .1..1..0..1. .0..0..0..1. .1..0..1..0
CROSSREFS
Cf. A295051.
Sequence in context: A128734 A006321 A371620 * A295375 A081554 A231109
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 13 2017
STATUS
approved