Changes between Initial Version and Version 3 of Ticket #17787


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Timestamp:
02/15/15 21:00:46 (6 years ago)
Author:
ncohen
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  • Ticket #17787

    • Property Status changed from new to needs_review
    • Property Commit changed from to b937842be6daaa63611f4ce4fef2238fcff65200
    • Property Branch changed from to u/ncohen/17787

  • Ticket #17787 – Description

    initial v3  
    88This graph is not an interval graph as it contains an asteroidal triple (1,5,7).
    99
    10 The fix is rather short: some 'partial' pq-trees were handled like 'full' ones and that was wrong. As an additional check, we get the expected [2] number of interval graphs up to n=9:
     10The fix is rather short: some 'partial' pq-trees were handled like 'full' ones and that was wrong. As an additional check, we get the expected [2] number of interval graphs up to n=9 (takes ~10mn)
     11
     12{{{
     13sage: n = 8
     14sage: count = [0]*(n+1)
     15sage: for g in graphs(n, augment='vertices',property= lambda x:x.is_interval()):
     16....:     count[g.order()] += 1
     17sage: count
     18[1, 1, 2, 4, 10, 27, 92, 369, 1807, 10344]
     19}}}
    1120
    1221Nathann