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

Author

R. H. Hardin, Feb 01 2016

Keywords

• nonn

Comments

Column 4 of A268327.

Examples

			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
		

Links

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

Crossrefs

Cf. A268327.

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)