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A036908 Number of different compact source directed animals with 1 point on the bottom line. 1

%I

%S 1,2,5,14,40,116,339,996,2937,8684,25729,76352,226868,674806,2008907,

%T 5984886,17841024,53212500,158784033,473995320,1415449578,4228149450,

%U 12633596331,37758241434,112873961079,337492122822,1009283640669,3018807519506,9030752740042

%N Number of different compact source directed animals with 1 point on the bottom line.

%H Harvey P. Dale, <a href="/A036908/b036908.txt">Table of n, a(n) for n = 1..1000</a>

%H Nickolas Hein, Jia Huang, <a href="https://arxiv.org/abs/1807.04623">Variations of the Catalan numbers from some nonassociative binary operations</a>, arXiv:1807.04623 [math.CO], 2018.

%F G.f.: x(1-3x+sqrt(1-2x-3x^2))/((1-3x)(3x-1+sqrt(1-2x-3x^2)).

%t CoefficientList[Series[x (1-3x+ Sqrt[1-2x-3x^2])/((1-3x)(3x-1+ Sqrt[ 1- 2x- 3x^2])),{x,0,30}],x] (* _Harvey P. Dale_, Jun 03 2012 *)

%K nonn

%O 1,2

%A _Louis Shapiro_

%E More terms from _Harvey P. Dale_, Jun 03 2012

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Last modified February 16 04:34 EST 2019. Contains 320140 sequences. (Running on oeis4.)