References to A002457

(2n+1)!/n!^2.
1, 6, 30, 140, 630, 2772, 12012, 51480, 218790, 923780, 3879876, 16224936

1 seqfan posts

Sun Jun 28 21:08:22 CEST 2009    [seqfan] Catalan-related sequences with floretions
Index of A-numbers in seqfan: by ascending order    by month    by frequency    by keyword
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