A209510 Half the number of (n+1)X8 0..2 arrays with every 2X2 subblock having two or four distinct clockwise edge differences

6561, 242889, 9225765, 353991129, 13642432110, 526815563193, 20362314816594, 787378099628577, 30452815417249224, 1177911989563198242, 45563556788314601670, 1762509641645545600089, 68178848629430688643791

Offset

1,1

Comments

Column 7 of A209511

Links

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

Formula

Empirical: a(n) = 105*a(n-1) -4473*a(n-2) +105654*a(n-3) -1580037*a(n-4) +16082595*a(n-5) -116408090*a(n-6) +616031475*a(n-7) -2425718097*a(n-8) +7181467374*a(n-9) -16063429749*a(n-10) +27150592284*a(n-11) -34525830041*a(n-12) +32730104655*a(n-13) -22785383754*a(n-14) +11380763892*a(n-15) -3932260752*a(n-16) +884206944*a(n-17) -115250048*a(n-18) +6527616*a(n-19)

Example

Some solutions for n=4
..1..2..0..1..2..0..2..0....1..2..0..1..0..1..2..1....0..1..0..1..0..1..2..0
..2..0..1..2..0..1..0..1....0..1..2..0..1..2..0..2....1..2..1..2..1..2..0..2
..0..1..2..1..2..0..1..2....1..0..1..2..0..1..2..0....2..1..2..1..2..0..1..0
..2..0..1..2..0..1..2..1....2..1..2..0..1..2..0..1....0..2..0..2..1..2..0..1
..0..1..2..0..1..2..0..2....0..2..0..2..0..1..2..0....1..0..2..0..2..0..2..0

Crossrefs

Sequence in context: A017380 A017500 A017632 * A016760 A203652 A016772

Adjacent sequences: A209507 A209508 A209509 * A209511 A209512 A209513

Keyword

nonn

Author

R. H. Hardin Mar 09 2012

Status

approved