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A227808
Number of rooted identity trees with n nodes and exactly 4 subtrees from the root.
2
2, 4, 13, 34, 91, 225, 571, 1403, 3466, 8468, 20703, 50389, 122673, 298090, 724433, 1759595, 4274819, 10385533, 25240007, 61358410, 149226407, 363077813, 883818374, 2152462147, 5244790003, 12786162151, 31187100089, 76108058977, 185825963102, 453940832229
OFFSET
11,1
LINKS
EXAMPLE
: o o :
: /( )\ /( )\ :
: / | | \ / | | \ :
: o o o o o o o o :
: /| | | | | | :
: o o o o o o o :
: | | | | :
: o o o o :
: | :
: n=11 o :
CROSSREFS
Column k=4 of A227774.
Sequence in context: A148228 A148229 A148230 * A148231 A148232 A148233
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 31 2013
STATUS
approved