A183786 Half the number of (n+1)X4 0..2 arrays with no 2X2 subblock having sum 4

1500, 57966, 2214457, 84888699, 3250564943, 124516635830, 4769141272937, 182672398106924, 6996783566736966, 267994941652776449, 10264877718803117731, 393170860146828537991, 15059436873638019867688

Offset

1,1

Comments

Column 3 of A183792

Links

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

Formula

Empirical: a(n)=17*a(n-1)+889*a(n-2)+67*a(n-3)-114442*a(n-4)+38222*a(n-5)+5710965*a(n-6)-8373409*a(n-7)-114051095*a(n-8)+222632076*a(n-9)+1029783661*a(n-10)-1946743843*a(n-11)-5282620167*a(n-12)+7274521160*a(n-13)+16742640966*a(n-14)-10412461098*a(n-15)-29378741112*a(n-16)-1262180872*a(n-17)+20149053824*a(n-18)+9992725504*a(n-19)+555859968*a(n-20)-154140672*a(n-21)

Example

Some solutions for 3X4
..2..1..0..1....0..2..0..2....0..1..0..1....0..2..0..0....2..1..1..1
..2..0..0..2....1..2..1..2....0..1..0..1....2..2..1..0....2..2..2..2
..2..2..0..1....0..2..2..0....0..2..0..1....2..1..2..0....1..1..1..1

Crossrefs

Sequence in context: A098191 A253509 A237136 * A181599 A181706 A092725

Adjacent sequences: A183783 A183784 A183785 * A183787 A183788 A183789

Keyword

nonn

Author

R. H. Hardin Jan 07 2011

Status

approved