{ "id": "math/0511636", "version": "v1", "published": "2005-11-25T20:23:39.000Z", "updated": "2005-11-25T20:23:39.000Z", "title": "Classification of small $(0,1)$ matrices", "authors": [ "Miodrag Živković" ], "comment": "45 pages. submitted to LAA", "categories": [ "math.CO" ], "abstract": "Denote by $A_n$ the set of square $(0,1)$ matrices of order $n$. The set $A_n$, $n\\le8$, is partitioned into row/column permutation equivalence classes enabling derivation of various facts by simple counting. For example, the number of regular $(0,1)$ matrices of order 8 is 10160459763342013440. Let $D_n$, $S_n$ denote the set of absolute determinant values and Smith normal forms of matrices from $A_n$. Denote by $a_n$ the smallest integer not in $D_n$. The sets $\\mathcal{D}_9$ and $\\mathcal{S}_9$ are obtained; especially, $a_9=103$. The lower bounds for $a_n$, $10\\le n\\le 19$, (exceeding the known lower bound $a_n\\ge 2f_{n-1}$, where $f_n$ is $n$th Fibonacci number) are obtained. Row/permutation equivalence classes of $A_n$ correspond to bipartite graphs with $n$ black and $n$ white vertices, and so the other applications of the classification are possible.", "revisions": [ { "version": "v1", "updated": "2005-11-25T20:23:39.000Z" } ], "analyses": { "subjects": [ "15A21", "15A36", "11Y55" ], "keywords": [ "classification", "permutation equivalence classes enabling derivation", "lower bound", "row/column permutation equivalence classes enabling", "th fibonacci number" ], "note": { "typesetting": "TeX", "pages": 45, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math.....11636Z" } } }