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A079221 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 five-fold application of Catalan Automorphisms A057511/A057512 (Deep rotation of general parenthesizations/plane trees). 4
1, 1, 1, 2, 0, 1, 3, 1, 0, 1, 5, 0, 0, 0, 1, 6, 2, 1, 0, 5, 1, 15, 0, 0, 0, 20, 0, 1, 36, 5, 0, 1, 65, 0, 0, 1, 108, 0, 2, 0, 190, 0, 0, 0, 1, 301, 11, 0, 0, 501, 0, 0, 0, 0, 1, 814, 0, 0, 0, 1265, 0, 0, 0, 0, 0, 1, 2080, 26, 3, 2, 3105, 1, 0, 0, 0, 5, 0, 1, 5223, 0, 0, 0, 7695, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

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

LINKS

Table of n, a(n) for n=0..89.

MAPLE

[seq(A079221(n), n=0..119)]; A079221 := n -> PFixedByA057511(A003056(n)+1, 5, A002262(n)+1);

CROSSREFS

The row sums equal to the left edge shifted left once = A079226 = fifth row of A079216 (the latter gives the Maple procedure PFixedByA057511). Cf. also A079217-A079222 and A003056 and A002262.

Sequence in context: A099557 A214576 A079217 * A168019 A026794 A137712

Adjacent sequences:  A079218 A079219 A079220 * A079222 A079223 A079224

KEYWORD

nonn,tabl

AUTHOR

Antti Karttunen Jan 03 2002

STATUS

approved

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Last modified May 23 12:58 EDT 2013. Contains 225588 sequences.