A207761 Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically

28, 784, 2654, 11509, 59252, 235872, 887114, 3488718, 13324700, 49528948, 184808314, 687726602, 2538842648, 9356257550, 34457742152, 126613738962, 464595415916, 1703705288482, 6242056357676, 22851249560906, 83609513888316

Offset

1,1

Comments

Column 7 of A207762

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -30*a(n-2) +101*a(n-3) -452*a(n-4) +1080*a(n-5) -2212*a(n-6) +7988*a(n-7) -14310*a(n-8) +18574*a(n-9) -74548*a(n-10) +97674*a(n-11) -59812*a(n-12) +477460*a(n-13) -408258*a(n-14) -76060*a(n-15) -2426098*a(n-16) +1052702*a(n-17) +1527766*a(n-18) +9776968*a(n-19) -978888*a(n-20) -7207648*a(n-21) -30286394*a(n-22) -3635038*a(n-23) +19889764*a(n-24) +70635534*a(n-25) +17114220*a(n-26) -37149004*a(n-27) -121787501*a(n-28) -35300157*a(n-29) +49526360*a(n-30) +154324589*a(n-31) +41825606*a(n-32) -49157144*a(n-33) -142598668*a(n-34) -27479092*a(n-35) +38216016*a(n-36) +96382504*a(n-37) +4500656*a(n-38) -23708240*a(n-39) -48440992*a(n-40) +7538688*a(n-41) +11797440*a(n-42) +18533248*a(n-43) -7068544*a(n-44) -3979392*a(n-45) -5485568*a(n-46) +3083776*a(n-47) +727552*a(n-48) +1075712*a(n-49) -813056*a(n-50) -5120*a(n-51) -122880*a(n-52) +161792*a(n-53) -20480*a(n-54) +8192*a(n-55) -16384*a(n-56) for n>60

Example

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

Crossrefs

Sequence in context: A207681 A207894 A207884 * A207168 A208012 A207789

Adjacent sequences: A207758 A207759 A207760 * A207762 A207763 A207764

Keyword

nonn

Author

R. H. Hardin Feb 19 2012

Status

approved