References to A000138

E.g.f. exp(-x^4/4)/(1-x).
1, 1, 2, 6, 18, 90, 540, 3780, 31500, 283500, 2835000, 31185000, 372972600

1 seqfan posts

Fri Oct 29 05:35:16 CEST 2010    [seqfan] Implementing first 500 sequences in Java
Index of A-numbers in seqfan: by ascending order    by month    by frequency    by keyword
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