cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A079219 Triangle T(n,d) (listed row-wise: T(1,1)=1, T(2,1)=1, T(2,2)=1, T(3,1)=2, T(3,2)=0, T(3,3)=1, ...) giving the number of n-edge general plane trees with root degree d that are fixed by the three-fold application of Catalan Automorphisms A057511/A057512 (Deep rotation of general parenthesizations/plane trees).

Original entry on oeis.org

1, 1, 1, 2, 0, 1, 3, 1, 3, 1, 8, 0, 9, 0, 1, 18, 2, 22, 0, 0, 1, 43, 0, 60, 0, 0, 0, 1, 104, 5, 159, 1, 0, 3, 0, 1, 273, 0, 428, 0, 0, 0, 0, 0, 1, 702, 14, 1143, 0, 1, 9, 0, 0, 0, 1, 1870, 0, 3114, 0, 0, 0, 0, 0, 0, 0, 1, 4985, 38, 8505, 2, 0, 28, 0, 0, 3, 0, 0, 1, 13562, 0, 23475, 0, 0, 0, 0
Offset: 0

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Author

Antti Karttunen Jan 03 2002

Keywords

Comments

Note: the counts given here are inclusive, i.e. T(n,d) includes also the count A079217(n,d).

Crossrefs

The row sums equal to the left edge shifted left once = A079224 = third row of A079216 (the latter gives the Maple procedure PFixedByA057511). Cf. also A079217-A079222 and A003056 and A002262.

Programs