

A131763


Series reversion of x(14x)/(1x) .


2



1, 3, 21, 183, 1785, 18651, 204141, 2310447, 26819121, 317530227, 3819724293, 46553474919, 573608632233, 7133530172619, 89423593269213, 1128765846337887, 14334721079385441, 183021615646831587
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OFFSET

0,2


COMMENTS

The Hankel transform of this sequence is 12^C(n+1,2) .
Number of Dyck npaths with two colors of up (U,u) and two colors of down (D,d) avoiding UD.  David Scambler, Jun 24 2013


REFERENCES

P. Barry, Embedding structures associated with Riordan arrays and moment matrices, arXiv preprint arXiv:1312.0583, 2013


LINKS

Table of n, a(n) for n=0..17.


FORMULA

a(n) = Sum_{k, 0<=k<=n}A086810(n,k)*3^k .
a(n)=(3/4)*A103211(n) for n>0 .


CROSSREFS

Sequence in context: A192946 A216171 A054879 * A006199 A083063 A012163
Adjacent sequences: A131760 A131761 A131762 * A131764 A131765 A131766


KEYWORD

nonn


AUTHOR

Philippe Deléham, Oct 29 2007, Nov 06 2007


EXTENSIONS

a(17) corrected by Mark van Hoeij, Jul 01 2010


STATUS

approved



