A207405 Number of 5Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 1 0 vertically

10, 100, 390, 1521, 4212, 11664, 26676, 61009, 123006, 248004, 456666, 840889, 1445192, 2483776, 4042440, 6579225, 10244610, 15952036, 23944030, 35940025, 52300380, 76108176, 107854812, 152843769, 211679286, 293162884, 397932402

Offset

1,1

Comments

Row 5 of A207403

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)

Example

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

Crossrefs

Sequence in context: A086115 A209652 A207072 * A207706 A207251 A208289

Adjacent sequences: A207402 A207403 A207404 * A207406 A207407 A207408

Keyword

nonn

Author

R. H. Hardin Feb 17 2012

Status

approved