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A202330
Number of (n+1) X 4 binary arrays with consecutive windows of two bits considered as a binary number nondecreasing in every row and column.
1
36, 82, 162, 289, 478, 746, 1112, 1597, 2224, 3018, 4006, 5217, 6682, 8434, 10508, 12941, 15772, 19042, 22794, 27073, 31926, 37402, 43552, 50429, 58088, 66586, 75982, 86337, 97714, 110178, 123796, 138637, 154772, 172274, 191218, 211681, 233742
OFFSET
1,1
COMMENTS
Column 3 of A202335.
LINKS
FORMULA
Empirical: a(n) = (1/12)*n^4 + (4/3)*n^3 + (83/12)*n^2 + (44/3)*n + 13.
Conjectures from Colin Barker, May 27 2018: (Start)
G.f.: x*(36 - 98*x + 112*x^2 - 61*x^3 + 13*x^4) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5).
(End)
EXAMPLE
Some solutions for n=5:
..0..0..0..1....0..0..0..0....0..0..0..1....0..0..1..0....0..0..1..0
..0..0..0..1....0..0..1..0....0..0..0..1....0..0..1..0....0..0..1..1
..0..0..0..1....0..0..1..0....0..0..0..1....0..0..1..0....0..0..1..1
..0..0..0..1....0..0..1..0....0..1..1..1....0..0..1..0....0..1..1..1
..0..0..1..1....0..0..1..0....1..1..1..1....0..0..1..1....0..1..1..1
..0..1..1..1....0..1..1..1....0..1..1..1....0..0..1..0....1..1..1..1
CROSSREFS
Cf. A202335.
Sequence in context: A341555 A084006 A254648 * A226264 A243804 A043183
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2011
STATUS
approved