A269655 Number of length-n 0..7 arrays with no adjacent pair x,x+1 repeated.
8, 64, 512, 4089, 32600, 259476, 2061940, 16359580, 129599404, 1025145474, 8097221352, 63866100432, 503041727344, 3956869283864, 31083352671872, 243863266575744, 1910824354782112, 14954229427038576, 116893085869240608
Offset: 1
Keywords
Examples
Some solutions for n=5 ..1. .4. .4. .0. .2. .2. .2. .7. .0. .3. .6. .4. .5. .3. .1. .0 ..1. .3. .4. .3. .2. .2. .7. .0. .3. .1. .5. .5. .5. .1. .6. .7 ..4. .5. .3. .0. .0. .5. .1. .3. .4. .1. .3. .0. .2. .0. .5. .4 ..4. .2. .4. .1. .2. .2. .3. .7. .3. .6. .4. .6. .4. .1. .1. .5 ..0. .6. .4. .7. .3. .6. .1. .3. .1. .2. .0. .7. .1. .5. .3. .0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
- R. H. Hardin, Empirical recurrence of order 64
Crossrefs
Cf. A269656.
Formula
Empirical recurrence of order 64 (see link above)
Comments