A197404 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,1,1,1 for x=0,1,2,3,4.
4, 20, 60, 358, 1626, 7232, 34717, 160988, 748843, 3514426, 16448990, 76889286, 359867470, 1684122959, 7879951514, 36879246800, 172597946528, 807735845097, 3780221117751, 17691605965676, 82797291928191, 387496301051514
Offset: 1
Keywords
Examples
Some solutions for n=4 ..1..0..0....1..0..0....0..0..0....1..0..0....1..0..1....1..1..0....0..0..0 ..2..1..1....2..0..0....0..2..1....1..1..2....1..2..1....0..1..1....1..1..1 ..0..2..1....1..2..1....2..1..2....0..2..1....0..0..0....0..1..2....2..1..3 ..0..0..0....0..0..1....1..0..0....0..0..0....1..1..1....1..2..0....0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..200
Formula
Empirical: a(n) = 4*a(n-1) +4*a(n-2) +8*a(n-3) -37*a(n-4) -13*a(n-5) -58*a(n-6) -814*a(n-7) -2710*a(n-8) -1095*a(n-9) +6385*a(n-10) +15988*a(n-11) +42018*a(n-12) +47855*a(n-13) +32250*a(n-14) -50035*a(n-15) -77306*a(n-16) -41809*a(n-17) -25413*a(n-18) -49387*a(n-19) -14658*a(n-20) +11927*a(n-21) +12328*a(n-22) +6216*a(n-23) +17403*a(n-24) +12464*a(n-25) -363*a(n-26) +6490*a(n-27) -2100*a(n-28) +61*a(n-29) -629*a(n-30) -131*a(n-31) +42*a(n-32) +a(n-33) +a(n-34)
Comments