A269408 Number of length-n 0..7 arrays with no repeated value greater than or equal to the previous repeated value.

8, 64, 504, 3948, 30744, 238224, 1837752, 14121282, 108123624, 825227424, 6279994728, 47663522844, 360868232424, 2726022470928, 20549497120776, 154606709405835, 1161096042133440, 8705061811230400, 65160664171875440

Offset: 1

Author

R. H. Hardin, Feb 25 2016

Keywords

• nonn

Comments

Column 7 of A269409.

Examples

			Some solutions for n=5
..6. .0. .0. .4. .7. .2. .6. .3. .2. .6. .6. .4. .4. .3. .1. .5
..6. .1. .7. .7. .1. .1. .3. .4. .0. .2. .6. .7. .2. .0. .1. .2
..7. .7. .6. .4. .5. .6. .4. .2. .5. .5. .5. .1. .4. .6. .2. .4
..5. .7. .5. .4. .1. .2. .3. .3. .5. .2. .1. .6. .5. .1. .0. .0
..0. .3. .1. .7. .7. .4. .3. .1. .1. .7. .0. .3. .3. .1. .3. .0
		

Links

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

Crossrefs

Cf. A269409.

Formula

Empirical: a(n) = 56*a(n-1) -1344*a(n-2) +17752*a(n-3) -135716*a(n-4) +545496*a(n-5) -463792*a(n-6) -4675336*a(n-7) [phone]*a(n-8) [phone]*a(n-9) -72913568*a(n-10) -123833976*a(n-11) [phone]*a(n-12) [phone]*a(n-13) [phone]*a(n-14) [phone]*a(n-15) [phone]*a(n-16)