A202372 Number of (n+2)X4 binary arrays avoiding patterns 001 and 111 in rows and columns

257, 824, 2293, 5677, 13751, 31240, 68965, 148281, 310793, 640839, 1299608, 2601118, 5148674, 10088995, 19604270, 37808312, 72431966, 137955751, 261370700, 492867363, 925469673, 1731093570, 3226750237, 5995509954, 11107634611

Offset

1,1

Comments

Column 2 of A202378

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +5*a(n-2) -12*a(n-3) -34*a(n-4) +30*a(n-5) +110*a(n-6) +16*a(n-7) -230*a(n-8) -171*a(n-9) +177*a(n-10) +360*a(n-11) +66*a(n-12) -172*a(n-13) -248*a(n-14) -135*a(n-15) -72*a(n-16) +182*a(n-17) +196*a(n-18) +148*a(n-19) -68*a(n-20) -39*a(n-21) -106*a(n-22) -13*a(n-23) -46*a(n-24) +29*a(n-25) -34*a(n-26) +16*a(n-27) -5*a(n-28) +42*a(n-29) +13*a(n-30) +22*a(n-31) -8*a(n-32) -6*a(n-33) -14*a(n-34) -3*a(n-35) -2*a(n-36) +2*a(n-37) +a(n-38) +a(n-39)

Example

Some solutions for n=7
..1..1..0..1....1..1..0..1....1..0..1..1....1..1..0..1....1..1..0..0
..1..0..1..1....0..0..0..0....0..1..1..0....1..0..1..0....0..1..1..0
..0..1..0..0....1..1..0..1....1..0..0..0....0..1..1..0....1..0..0..0
..1..0..1..0....0..1..0..1....0..1..0..0....1..0..0..0....1..1..0..0
..0..1..0..0....1..0..0..0....0..0..0..0....1..0..0..0....0..1..0..0
..1..0..0..0....1..1..0..0....0..0..0..0....0..0..0..0....1..0..0..0
..1..1..0..0....0..1..0..0....0..0..0..0....1..0..0..0....0..1..0..0
..0..1..0..0....1..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..0..0....1..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

Crossrefs

Sequence in context: A229856 A208178 A105131 * A363715 A036549 A352983

Adjacent sequences: A202369 A202370 A202371 * A202373 A202374 A202375

Keyword

nonn

Author

R. H. Hardin Dec 18 2011

Status

approved