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A269655
Number of length-n 0..7 arrays with no adjacent pair x,x+1 repeated.
1
8, 64, 512, 4089, 32600, 259476, 2061940, 16359580, 129599404, 1025145474, 8097221352, 63866100432, 503041727344, 3956869283864, 31083352671872, 243863266575744, 1910824354782112, 14954229427038576, 116893085869240608
OFFSET
1,1
COMMENTS
Column 7 of A269656.
FORMULA
Empirical recurrence of order 64 (see link above)
EXAMPLE
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
CROSSREFS
Cf. A269656.
Sequence in context: A269689 A269493 A269775 * A250360 A190130 A125908
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 02 2016
STATUS
approved