A266933 Number of nX6 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.
2, 6, 19, 82, 429, 2577, 15850, 96503, 555060, 2977370, 14782970, 68041108, 291292442, 1165800099, 4383605127, 15564591521, 52423001756, 168200350788, 516045791503, 1519124991181
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..0..0..0..0....0..0..0..0..1..1....0..0..0..0..0..1....0..0..0..0..0..0 ..0..0..0..0..0..1....1..1..1..1..0..0....0..0..0..1..1..0....0..0..1..1..1..1 ..0..0..0..0..1..0....1..1..1..1..0..0....1..1..1..0..0..0....1..1..0..0..1..1 ..1..1..1..1..0..0....1..1..1..1..1..1....1..1..1..0..0..0....1..1..1..1..0..0
Crossrefs
Cf. A266935.
Comments