login
A227594
T(n,k)=Number of nXk 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X(k+1) binary array having nonzero determinant
4
2, 4, 4, 8, 16, 8, 16, 64, 64, 16, 32, 256, 496, 256, 32, 64, 1024, 3840, 3840, 1024, 64, 128, 4096, 29676, 56928, 29676, 4096, 128, 256, 16384, 229140, 841984, 841984, 229140, 16384, 256, 512, 65536, 1768536, 12420672, 23778768, 12420672, 1768536
OFFSET
1,1
COMMENTS
Table starts
...2......4.........8..........16.............32..............64
...4.....16........64.........256...........1024............4096
...8.....64.......496........3840..........29676..........229140
..16....256......3840.......56928.........841984........12420672
..32...1024.....29676......841984.......23778768.......668273468
..64...4096....229140....12420672......668273468.....35695226048
.128..16384...1768536...182940432....18728235880...1898924859202
.256..65536..13647884..2693032800...524299291340.100857512952616
.512.262144.105314460.39634170368.14670617834075
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 4*a(n-1)
k=3: [order 11]
k=4: [order 63]
EXAMPLE
Some solutions for n=4 k=4
..1..0..1..1....1..0..0..0....0..1..1..1....1..0..1..0....0..0..0..0
..0..1..1..0....0..1..1..1....1..1..0..0....1..1..0..0....0..1..0..0
..0..1..1..0....1..1..0..1....1..0..0..0....1..1..0..1....1..1..0..0
..0..1..1..1....0..0..1..0....0..0..1..0....1..0..1..0....1..0..0..0
CROSSREFS
Column 1 is A000079
Column 2 is A000302
Sequence in context: A189111 A181217 A223569 * A321241 A290128 A291778
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Jul 17 2013
STATUS
approved