A267668 Number of 3Xn 0..1 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.
4, 32, 108, 500, 1372, 5324, 13500, 48668, 119164, 415292, 1000188, 3429500, 8193532, 27871484, 66325500, 224727548, 533731324, 1804870652, 4282396668, 14467221500, 34309431292, 115850907644, 274676629500, 927260024828
Offset: 1
Keywords
Examples
Some solutions for n=8 ..0..1..0..1..0..1..0..1....0..1..0..1..0..0..1..1....0..1..0..1..0..1..0..1 ..1..0..1..0..1..0..1..1....0..0..1..0..1..1..0..1....0..0..1..0..1..0..1..1 ..1..1..0..1..0..0..1..0....1..0..1..0..1..1..0..1....1..0..1..1..0..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A267667.
Formula
Empirical: a(n) = a(n-1) +14*a(n-2) -14*a(n-3) -56*a(n-4) +56*a(n-5) +64*a(n-6) -64*a(n-7)
Comments