counting intersecting cliques of same size - MathOverflow most recent 30 from http://mathoverflow.net2013-05-26T00:22:55Zhttp://mathoverflow.net/feeds/question/107627http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/107627/counting-intersecting-cliques-of-same-sizecounting intersecting cliques of same sizevzn2012-09-19T23:13:55Z2012-09-19T23:13:55Z
<p>(earlier tried to count the following but came up with a wrong formula so will just ask the direct question without proposing a formula 1st.)</p>
<p>given: a graph of $m$ vertices, $\binom{m}{2}$ edges and a fixed clique of $\binom{n}{2}$ edges. </p>
<blockquote>
<ul>
<li>how many other cliques on this graph are there of size $\binom{n}{2}$ edges that have at least one edge in common with the first fixed clique? (ie counting two cliques of same size on same graph, one fixed, the other variably-placed, with intersecting/shared edges, not disjoint.)</li>
<li>prefer an end formula without binomial coefficient expressions in it. an asymptotic estimate may be ok.</li>
<li>has someone seen this formula in a paper or book somewhere? esp interested in uses of it in comp sci refs/books/papers or extremal graph/set theory.</li>
</ul>
</blockquote>
<p>(have a rough idea of how to count this but got messed up in the details.)</p>