Number of forests of labeled rooted trees of height at most 1, with 2n labels, n of which are used for root nodes and any root may contain >= 1 labels.
A273661
Number of forests of labeled rooted trees of height at most 1, with 2n labels, n of which are used for root nodes and any root may contain >= 1 labels.
Terms
- a(0) =1a(1) =2a(2) =30a(3) =1040a(4) =59850a(5) =5020092a(6) =568136184a(7) =82506827832
External references
- oeis: A273661