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Unlabeled super-Catalan numbers: patterns of nonintersecting chords joining unlabeled points on a circle, triangle decomposed by number of chords.
1

%I #10 Jul 25 2021 13:57:20

%S 1,1,1,1,2,3,1,2,7,7,1,3,15,33,22,1,3,24,94,136,66,1,4,41,218,525,552,

%T 217,1,4,57,440,1517,2673,2233,715,1,5,86,804,3748,9439,12917,8807,

%U 2438

%N Unlabeled super-Catalan numbers: patterns of nonintersecting chords joining unlabeled points on a circle, triangle decomposed by number of chords.

%C Decomposition of A183757 by number of chords (pairs of parentheses). Row sums are A183757. See A183757 for description.

%C Triangle is

%C 1

%C 1 1

%C 1 2 3

%C 1 2 7 7

%C 1 3 15 33 22

%C 1 3 24 94 136 66

%C ...

%C Right diagonal is apparently A007595.

%Y Decomposition of A183757.

%Y Cf. analogous decomposition of super-Catalan numbers in triangle A033282.

%K nonn,tabl,more

%O 1,5

%A _David Scambler_, Jan 06 2011