A268323 Number of length-(n+1) 0..4 arrays with new values introduced in sequential order, and with new repeated values introduced in sequential order, both starting with zero.

2, 4, 11, 33, 113, 418, 1644, 6729, 28306, 121290, 526528, 2307684, 10189912, 45272176, 202209217, 907511800, 4091094290, 18521091171, 84191453893, 384234672892, 1760416403153, 8096423923987, 37376700482989, 173184754445281

Offset

1,1

Comments

Column 4 of A268327.

Links

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

Formula

Empirical: a(n) = 30*a(n-1) -383*a(n-2) +2665*a(n-3) -10530*a(n-4) +20413*a(n-5) +1810*a(n-6) -87142*a(n-7) +111699*a(n-8) +116304*a(n-9) -292159*a(n-10) -83751*a(n-11) +371556*a(n-12) +93673*a(n-13) -257980*a(n-14) -122812*a(n-15) +60076*a(n-16) +59180*a(n-17) +15912*a(n-18) +1440*a(n-19)

Example

Some solutions for n=10
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....1....0....1....1....1....1....0....1....0....0....1....0....1....1
..2....0....2....1....2....0....0....0....0....0....0....1....0....0....2....2
..0....2....0....0....1....2....0....0....1....2....1....2....1....1....0....0
..1....3....0....1....3....3....2....2....2....3....1....3....2....1....1....0
..0....2....3....2....2....2....3....1....1....4....1....1....0....2....0....0
..3....4....0....0....3....4....0....3....2....2....2....2....1....2....3....3
..4....0....3....2....2....0....0....1....3....0....1....1....2....3....1....1
..0....2....0....1....1....1....0....0....4....3....1....0....3....4....0....4
..1....1....0....1....4....4....4....0....0....1....2....1....4....3....4....0
..4....0....4....0....3....3....2....4....4....0....0....2....3....4....0....3

Crossrefs

Cf. A268327.

Sequence in context: A249945 A208799 A340329 * A268324 A268325 A268326

Adjacent sequences: A268320 A268321 A268322 * A268324 A268325 A268326

Keyword

nonn

Author

R. H. Hardin, Feb 01 2016

Status

approved