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 A225824 The number of increasing rooted identity trees. 0
 1, 1, 1, 4, 8, 38, 206, 1200, 7034, 53012, 465190, 4072948, 40967916, 438348328, 5113450320, 63135973560, 835727519000, 11736948927176, 175225673352928 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Unlabeled rooted identity trees are counted by A004111.  An increasing tree is a labeled tree such that any path from the root to each node is increasing. The first 8 terms are A032301(1..8).  The 9th term is A032301(9) plus the 210 increasing labelings of the tree shown in the example. LINKS EXAMPLE There are 210 increasing labelings for this identity tree: ..........0............ ........./ \........... ........0   0.......... ......./   / \......... ......0   0   0........ ...../    |     ....... ....0     0     ....... .../            ....... ..0             ....... CROSSREFS Cf. A032305. Sequence in context: A208820 A032301 A032213 * A032317 A032226 A001889 Adjacent sequences:  A225821 A225822 A225823 * A225825 A225826 A225827 KEYWORD nonn,more AUTHOR Geoffrey Critzer, Jul 30 2013 EXTENSIONS a(12)-a(19) from Alois P. Heinz, Aug 02 2013 STATUS approved

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Last modified December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)