A085685 Triangle read by rows: T(n,k), n >= 0, 0 <= k <= n, is size of maximal 1-transposition-correcting code formed using binary vectors of length n and weight k. The end-around transposition is allowed.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 3, 6, 3, 2, 1, 1, 2, 4, 7, 7, 4, 2, 1, 1, 2, 6, 10, 12, 10, 6, 2, 1, 1, 3, 7, 18, 21, 21, 18, 7, 3, 1, 1, 3, 9, 21, 33, 37, 33, 21, 9, 3, 1, 1, 3, 11, 28, 52, 63, 63, 52, 28, 11, 3, 1

Offset

0,18

Links

Table of n, a(n) for n=0..77.

N. J. A. Sloane, Challenge Problems: Independent Sets in Graphs

Example

Triangle begins
1
1 1
1 1 1
1 1 1 1
1 1 1 1 1
1 1 2 2 1 1

Crossrefs

Row sums are A057657.

Sequence in context: A027926 A114730 A031282 * A267632 A112465 A112468

Adjacent sequences: A085682 A085683 A085684 * A085686 A085687 A085688

Keyword

nonn,tabl

Author

N. J. A. Sloane, Jul 17 2003

Extensions

Row 10 from Brian Borchers (borchers(AT)nmt.edu), Apr 14 2005

Row 11 from Brian Borchers (borchers(AT)nmt.edu), Nov 04 2009

Status

approved