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A222023
Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..4 array extended with zeros and convolved with 1,3,3,1
1
2, 3, 4, 7, 11, 16, 26, 42, 65, 105, 168, 265, 424, 675, 1070, 1707, 2715, 4315, 6875, 10937, 17399, 27704, 44080, 70145, 111654, 177672, 282755, 450022, 716152, 1139735, 1813879, 2886645, 4594007, 7311215, 11635384, 18517300, 29469544
OFFSET
1,1
COMMENTS
Column 4 of A222027
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +2*a(n-3) -3*a(n-4) -2*a(n-5) +a(n-6) +3*a(n-7) +2*a(n-8) -5*a(n-9) -2*a(n-10) -a(n-11) +6*a(n-12) +a(n-13) -2*a(n-14) -4*a(n-15) -a(n-16) +4*a(n-17) +2*a(n-18) +3*a(n-19) -6*a(n-20) -3*a(n-21) +9*a(n-23) +2*a(n-24) -6*a(n-25) -5*a(n-26) +8*a(n-28) -a(n-30) -6*a(n-31) -a(n-32) +5*a(n-33) +4*a(n-34) -a(n-35) -6*a(n-36) +7*a(n-38) -2*a(n-39) -6*a(n-40) -4*a(n-41) +8*a(n-42) +2*a(n-43) -5*a(n-44) -2*a(n-45) +3*a(n-46) +4*a(n-47) -3*a(n-48) -a(n-49) +a(n-51)
EXAMPLE
Some solutions for n=7, one extended zero followed by filtered positions
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....1....1....1....1....1....1....0....1....0....0....0....1....0....0....0
..0....0....0....0....0....0....0....1....0....0....1....0....0....0....0....0
..0....0....1....1....0....0....0....0....0....0....0....1....0....0....0....0
..0....1....0....0....0....0....1....0....1....1....1....0....0....0....1....0
..0....0....0....0....1....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....1....0....1....1....0....0....0....0....0....0....1
..0....1....1....0....0....0....0....0....0....1....0....1....1....1....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
CROSSREFS
Sequence in context: A025048 A017987 A337495 * A221997 A221998 A165407
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 05 2013
STATUS
approved