A188304 Number of (n+1)X3 binary arrays with every 2X2 subblock sum equal to exactly one or two horizontal and vertical neighbor 2X2 subblock sums

24, 128, 664, 3036, 14832, 71888, 348728, 1694376, 8227500, 39976476, 194234820, 943833852, 4586483788, 22288261956, 108312977948, 526368362348, 2558010734684, 12431317914584, 60413417049308, 293596320376924

Offset

1,1

Comments

Column 2 of A188311

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=a(n-1)+17*a(n-2)+32*a(n-3)+2*a(n-4)-284*a(n-5)-1025*a(n-6)-1715*a(n-7)-1309*a(n-8)+3270*a(n-9)+15670*a(n-10)+33291*a(n-11)+51546*a(n-12)+61522*a(n-13)+46152*a(n-14)+54466*a(n-15)+141786*a(n-16)+299077*a(n-17)+512525*a(n-18)+124327*a(n-19)-1622071*a(n-20)-5412149*a(n-21)-11353672*a(n-22)-16599218*a(n-23)-16801594*a(n-24)-5985596*a(n-25)+18904065*a(n-26)+52984881*a(n-27)+82457676*a(n-28)+85772060*a(n-29)+47094373*a(n-30)-30021951*a(n-31)-116777988*a(n-32)-166409526*a(n-33)-146890040*a(n-34)-57288128*a(n-35)+57683368*a(n-36)+139661440*a(n-37)+157703584*a(n-38)+94438048*a(n-39)+8689664*a(n-40)-68850816*a(n-41)-91959296*a(n-42)-59136512*a(n-43)-26745856*a(n-44)+23861248*a(n-45)+29249536*a(n-46)+28721152*a(n-47)+3801088*a(n-48)-9109504*a(n-49)+9699328*a(n-50)-14680064*a(n-51)-3145728*a(n-52)+4194304*a(n-53)

Example

Some solutions for 5X3
..1..0..0....0..0..0....0..1..1....0..0..0....1..0..1....1..1..0....0..1..0
..1..1..0....0..1..0....1..0..0....1..0..1....0..0..0....0..1..1....1..0..1
..1..0..0....1..1..1....1..1..1....0..1..1....1..1..0....1..1..1....0..0..0
..0..0..1....1..1..1....0..1..1....1..0..1....0..0..0....0..1..1....0..1..0
..1..1..0....0..1..0....1..1..1....1..1..1....1..1..0....1..1..1....1..1..1

Crossrefs

Sequence in context: A305159 A326367 A182186 * A167981 A185490 A293365

Adjacent sequences: A188301 A188302 A188303 * A188305 A188306 A188307

Keyword

nonn

Author

R. H. Hardin Mar 27 2011

Status

approved