[seqfan] Re: Q on g.f. A138164

[Paul D Hanna]

Richard, 
     Good catch.  The formula should read: 
  
"G.f.: 1/(1-v-v^2) where v=(2/sqrt(3))*sin(arcsin(x*3*sqrt(3)/2)/3) is the series reversion of x*(1-x^2); ..."
 
(i.e., the second 'sin' should be 'arcsin') 
and a reference to A001764 would be in order since 
v = Sum_{n>=1} A001764(n-1)*x^(2*n-1). 
    Paul 
 
---------- Original Message ----------
From: "Richard J. Mathar" <mathar at mpia-hd.mpg.de>
To: seqfan at seqfan.eu
Subject: [seqfan] Q on g.f. A138164
Date: Mon, 23 Feb 2015 23:21:39 +0100

Is the generating function in http://oeis.org/A138164 correct?
The Maple implementation

vx := 2/sqrt(3)*sin(sin(x*3*sqrt(3)/2)/3) ;
A138164 := proc(n)
        1/(1-vx-vx^2) ;
        coeftayl(%,x=0,n) ;
end proc:
seq(%(n),n=0..13) ;

generates fractions from the power(x^3) on.

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