A221994 Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..3 array extended with zeros and convolved with 1,4,6,4,1

2, 3, 4, 6, 10, 15, 22, 36, 56, 84, 135, 211, 325, 510, 797, 1234, 1930, 3015, 4685, 7316, 11420, 17781, 27736, 43274, 67431, 105156, 164021, 255685, 398698, 621785, 969445, 1511643, 2357276, 3675552, 5731237, 8937024, 13935318, 21729235, 33882957

Offset

1,1

Comments

Column 3 of A221999

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = a(n-1) +a(n-3) +a(n-6) +3*a(n-9) -2*a(n-10) -a(n-13) -a(n-15) -a(n-16) -2*a(n-18) -2*a(n-21) -4*a(n-24) +a(n-25) +a(n-26) -7*a(n-27) +3*a(n-28) -2*a(n-30) +a(n-31)

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....0....1....0....0....1....0....0....0....0....1....0....0....0....1
..0....0....1....0....0....0....0....0....0....0....0....0....1....1....0....0
..1....0....0....0....0....0....0....0....0....1....1....0....0....0....1....0
..0....0....0....0....0....0....0....0....1....0....0....1....1....0....0....1
..0....0....0....0....0....0....1....0....0....0....0....0....0....0....1....0
..0....0....1....0....0....1....0....0....1....1....0....0....0....0....0....0
..1....1....0....0....0....0....0....1....0....0....0....0....0....1....0....1
..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

Crossrefs

Sequence in context: A206742 A221992 A221993 * A222021 A186426 A018062

Adjacent sequences: A221991 A221992 A221993 * A221995 A221996 A221997

Keyword

nonn

Author

R. H. Hardin Feb 03 2013

Status

approved