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A124778
Number of unlabeled unordered rooted forests associated with compositions in standard order.
0
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1
OFFSET
0,11
COMMENTS
The standard order of compositions is given by A066099.
The k-th term of the composition is the number of objects at height k; in particular, the first term is the number of trees.
EXAMPLE
Composition number 11 is 2,1,1; there is only 1 forest associated with this (shown below), so a(11) = 1.
O..
|..
O..
|..
O.O
The table starts:
1
1
1 1
1 1 1 1
1 1 2 1 1 1 1 1
CROSSREFS
Cf. A066099, A011782 (row lengths), A000081 (row sums).
Sequence in context: A356428 A158819 A031279 * A037831 A188169 A107039
KEYWORD
more,nonn,tabf
AUTHOR
STATUS
approved