A207766 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically.

21, 441, 1087, 6459, 21547, 56651, 235872, 862146, 2629798, 9529570, 34708948, 114255562, 396908066, 1416972222, 4828733870, 16634895736, 58487207221, 201993811973, 696619145912, 2429011369708, 8423471768055, 29119549204363

Offset

1,1

Comments

Row 6 of A207762.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -3*a(n-2) +47*a(n-3) -100*a(n-4) +68*a(n-5) -729*a(n-6) +1351*a(n-7) -599*a(n-8) +5751*a(n-9) -10798*a(n-10) +4250*a(n-11) -27354*a(n-12) +54520*a(n-13) -24176*a(n-14) +83574*a(n-15) -172480*a(n-16) +85820*a(n-17) -163088*a(n-18) +335152*a(n-19) -176096*a(n-20) +192808*a(n-21) -384288*a(n-22) +203280*a(n-23) -123648*a(n-24) +236544*a(n-25) -122496*a(n-26) +32640*a(n-27) -59904*a(n-28) +29952*a(n-29) for n>31.

Example

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

Crossrefs

Cf. A207762.

Sequence in context: A092499 A207776 A207273 * A207733 A208692 A207562

Adjacent sequences: A207763 A207764 A207765 * A207767 A207768 A207769

Keyword

nonn

Author

R. H. Hardin, Feb 19 2012

Status

approved