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A232227
Triangle read by rows: T(n,k) = number of crossing connected diagrams in a disk having n crossings and k chords.
2
1, 0, 8, 0, 1, 82, 0, 0, 43, 868, 0, 0, 11, 920, 9726, 0, 0, 1, 590, 15524, 113536, 0, 0, 0, 243, 15904, 243040, 1366570
OFFSET
1,3
LINKS
V. Pilaud and J. Rué, Analytic combinatorics of chord and hyperchord diagrams with k crossings, arXiv preprint arXiv:1307.6440 [math.CO], 2013.
EXAMPLE
Triangle begins:
1;
0, 8;
0, 1, 82;
0, 0, 43, 868;
0, 0, 11, 920, 9726;
0, 0, 1, 590, 15524, 113536;
0, 0, 0, 243, 15904, 243040, 1366570;
...
CROSSREFS
Cf. A232226 (row sums), A232225.
Sequence in context: A195447 A160389 A011104 * A322231 A261168 A329086
KEYWORD
nonn,tabl,more
AUTHOR
N. J. A. Sloane, Nov 22 2013
STATUS
approved