A183811 T(n,k)=1/16 the number of (n+1)X(k+1) binary arrays with no 2X2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor

1, 3, 3, 9, 13, 9, 27, 55, 55, 27, 81, 237, 322, 237, 81, 243, 1011, 1953, 1953, 1011, 243, 729, 4341, 11619, 16953, 11619, 4341, 729, 2187, 18567, 70044, 143191, 143191, 70044, 18567, 2187, 6561, 79605, 418925, 1232595, 1701473, 1232595, 418925, 79605

Offset

1,2

Comments

Table starts

.....1.......3........9.........27...........81............243..............729

.....3......13.......55........237.........1011...........4341............18567

.....9......55......322.......1953........11619..........70044...........418925

....27.....237.....1953......16953.......143191........1232595.........10494847

....81....1011....11619.....143191......1701473.......20745787........249227639

...243....4341....70044....1232595.....20745787......360549804.......6153770375

...729...18567...418925...10494847....249227639.....6153770375.....148654946039

..2187...79605..2518389...89998565...3023598287...106324742825....3645190453457

..6561..340803.15091626..768481445..36466869997..1823862776230...88602958444787

.19683.1460349.90619253.6579905737.441485256003.31435034643715.2166253373649057

Links

R. H. Hardin, Table of n, a(n) for n = 1..143

Example

Some solutions with upper left block zero for 4X3
..0..0..1....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1....0..0..1
..0..0..1....0..0..1....0..0..1....0..0..0....0..0..1....0..0..1....0..0..1
..0..1..0....1..1..1....1..1..0....0..1..1....1..0..1....1..0..0....1..0..0
..1..1..0....0..1..1....0..1..0....1..1..0....0..1..1....1..1..0....1..1..1

Crossrefs

Column 1 is A000244(n-1)

Sequence in context: A066314 A083336 A225436 * A303640 A091328 A348402

Adjacent sequences: A183808 A183809 A183810 * A183812 A183813 A183814

Keyword

nonn,tabl

Author

R. H. Hardin Jan 07 2011

Status

approved