A207073 Number of 6Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically

12, 144, 636, 2709, 13132, 54684, 210118, 818892, 3093184, 11234900, 40417797, 143649720, 501215991, 1730494710, 5926924410, 20097642000, 67608559928, 226048464005, 751020224850, 2480966742240, 8157248135323, 26701216937370

Offset

1,1

Comments

Row 6 of A207068

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -54*a(n-2) +233*a(n-3) -1050*a(n-4) +3640*a(n-5) -11089*a(n-6) +35920*a(n-7) -99056*a(n-8) +242196*a(n-9) -639700*a(n-10) +1478924*a(n-11) -3032625*a(n-12) +6937737*a(n-13) -13824516*a(n-14) +24253259*a(n-15) -50278733*a(n-16) +87539747*a(n-17) -132541709*a(n-18) +260941029*a(n-19) -396839415*a(n-20) +519631693*a(n-21) -1027805897*a(n-22) +1337808121*a(n-23) -1514124337*a(n-24) +3218760589*a(n-25) -3412085747*a(n-26) +3355166175*a(n-27) -8263816626*a(n-28) +6517423098*a(n-29) -5746972973*a(n-30) +17642944576*a(n-31) -8835559237*a(n-32) +7802190211*a(n-33) -31325339864*a(n-34) +6972531771*a(n-35) -8828587935*a(n-36) +45717150475*a(n-37) +979431933*a(n-38) +8943733407*a(n-39) -53851890004*a(n-40) -11614620112*a(n-41) -8419996657*a(n-42) +50138993624*a(n-43) +17699423160*a(n-44) +6843857724*a(n-45) -35927029036*a(n-46) -15514917704*a(n-47) -4156136536*a(n-48) +19141800016*a(n-49) +8558709104*a(n-50) +1634054400*a(n-51) -7184578560*a(n-52) -2844288000*a(n-53) -292665600*a(n-54) +1686528000*a(n-55) +473472000*a(n-56) -207360000*a(n-58)

Example

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

Crossrefs

Sequence in context: A207125 A207946 A209653 * A207406 A207707 A207252

Adjacent sequences: A207070 A207071 A207072 * A207074 A207075 A207076

Keyword

nonn

Author

R. H. Hardin Feb 14 2012

Status

approved