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A269618
Number of length-n 0..7 arrays with no repeated value differing from the previous repeated value by other than plus two, zero or minus 1.
1
8, 64, 512, 4053, 31822, 248143, 1923796, 14840928, 113998742, 872397577, 6654286340, 50608816911, 383908730032, 2905532655620, 21944295375268, 165426094919204, 1244944198391978, 9354631892435631, 70193014149728040
OFFSET
1,1
COMMENTS
Column 7 of A269619.
LINKS
FORMULA
Empirical: a(n) = 63*a(n-1) -1756*a(n-2) +28364*a(n-3) -291578*a(n-4) +1965390*a(n-5) -8566706*a(n-6) +22451548*a(n-7) -27837343*a(n-8) -2892449*a(n-9) +25243250*a(n-10) +17146752*a(n-11) +6127748*a(n-12) +1523522*a(n-13) +264748*a(n-14) +31542*a(n-15) +2437*a(n-16) +91*a(n-17)
EXAMPLE
Some solutions for n=5
..2. .3. .7. .7. .2. .5. .4. .2. .0. .6. .3. .1. .4. .2. .6. .0
..5. .1. .6. .5. .6. .0. .4. .3. .0. .7. .1. .6. .7. .7. .4. .1
..4. .2. .1. .5. .2. .1. .5. .2. .6. .7. .0. .2. .1. .1. .6. .2
..6. .5. .2. .7. .7. .1. .0. .1. .1. .5. .5. .4. .1. .0. .0. .6
..1. .4. .2. .2. .0. .4. .1. .3. .5. .3. .7. .7. .2. .3. .3. .7
CROSSREFS
Cf. A269619.
Sequence in context: A228981 A222388 A222937 * A269582 A269434 A269689
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 01 2016
STATUS
approved