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A224154
Number of nX4 0..1 arrays with diagonals and rows unimodal and antidiagonals nondecreasing
1
11, 56, 187, 574, 1783, 5657, 18408, 61140, 205390, 694018, 2350061, 7961090, 26964678, 91303265, 309082754, 1046163241, 3540718751, 11983122960, 40555030532, 137252283821, 464510611475, 1572073476421, 5320479934245
OFFSET
1,1
COMMENTS
Column 4 of A224158
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -5*a(n-2) -2*a(n-3) -3*a(n-4) +18*a(n-5) -18*a(n-6) +27*a(n-7) -3*a(n-8) -4*a(n-9) -8*a(n-11) -6*a(n-12) -6*a(n-13) for n>14
EXAMPLE
Some solutions for n=3
..0..0..0..0....1..1..0..0....1..1..1..0....1..1..1..1....0..1..0..0
..1..0..0..0....1..1..0..0....1..1..0..0....1..1..1..1....1..1..1..0
..1..1..1..1....1..1..1..0....1..1..1..0....1..1..1..0....1..1..0..0
CROSSREFS
Sequence in context: A275643 A341405 A223773 * A079547 A034264 A051946
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2013
STATUS
approved