A268322 Number of length-(n+1) 0..3 arrays with new values introduced in sequential order, and with new repeated values introduced in sequential order, both starting with zero.

2, 4, 11, 32, 102, 337, 1148, 3984, 14030, 49973, 179735, 652010, 2383857, 8779485, 32555471, 121497802, 456178652, 1722502343, 6538543106, 24942393310, 95581407132, 367817900179, 1420912978925, 5508514801624, 21423891255215

Offset

1,1

Comments

Column 3 of A268327.

Links

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

Formula

Empirical: a(n) = 15*a(n-1) -83*a(n-2) +181*a(n-3) +20*a(n-4) -632*a(n-5) +445*a(n-6) +849*a(n-7) -637*a(n-8) -673*a(n-9) +208*a(n-10) +260*a(n-11) +48*a(n-12)

Example

Some solutions for n=10
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....0....0....1....1....1....1....1....0....1....1....1....0....0....0
..2....0....0....0....0....2....2....2....0....1....2....2....2....1....0....1
..1....1....1....0....2....3....1....1....0....2....1....0....1....2....1....1
..3....2....2....1....1....2....0....0....0....3....3....0....2....0....1....1
..2....1....0....0....2....0....3....2....1....1....0....2....0....2....2....1
..3....2....3....2....0....1....2....3....0....0....0....1....1....3....0....1
..0....3....0....3....2....0....0....0....1....1....1....2....0....2....1....2
..0....0....0....1....1....3....1....1....1....2....1....0....1....1....1....3
..0....0....0....3....2....0....3....2....0....0....0....3....0....2....0....0
..1....1....0....2....0....0....2....1....2....0....3....1....1....0....0....0

Crossrefs

Cf. A268327.

Sequence in context: A135339 A148170 A156043 * A148171 A318644 A113774

Adjacent sequences: A268319 A268320 A268321 * A268323 A268324 A268325

Keyword

nonn

Author

R. H. Hardin, Feb 01 2016

Status

approved