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A300771
Number of nX3 0..1 arrays with every element equal to 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
0, 2, 3, 11, 32, 102, 330, 1059, 3418, 11023, 35561, 114744, 370251, 1194696, 3854994, 12439181, 40138345, 129517277, 417922738, 1348541219, 4351434893, 14041088118, 45307389076, 146196612400, 471743129235, 1522207498886, 4911816468097
OFFSET
1,2
COMMENTS
Column 3 of A300776.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +3*a(n-3) -3*a(n-4) +5*a(n-5) -2*a(n-6) -11*a(n-7) -13*a(n-8) +11*a(n-9) -2*a(n-10) -5*a(n-11) +a(n-12) +5*a(n-13) -4*a(n-14) +a(n-15)
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..0. .0..0..1. .0..0..1. .0..0..1. .0..0..1. .0..0..1
..0..1..1. .0..0..1. .0..1..1. .0..1..1. .0..1..1. .0..1..1. .0..1..1
..1..1..1. .0..1..1. .0..0..0. .0..0..0. .0..1..1. .1..1..1. .0..1..1
..0..0..1. .0..1..0. .1..1..0. .0..0..1. .0..1..0. .1..1..0. .0..0..1
..0..1..1. .0..0..0. .1..0..0. .0..1..1. .0..0..0. .1..0..0. .0..1..1
CROSSREFS
Cf. A300776.
Sequence in context: A144056 A268687 A062630 * A296005 A374310 A159458
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 12 2018
STATUS
approved