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Numerators are given under A120996.
See A120996 for details and a W. Lang link found there for the definition of four p-families of such scaled Catalan sums.
Table of n, a(n) for n=0..18.
a(n)=denominator(r(n)) with r(n) := rI(p=1,n) = sum(C(k)/L(2)^(2*k),k=0..n), with Lucas L(2)=3 and C(k):=A000108(k) (Catalan).
Sequence in context: A254435 A228972 A125947 * A125630 A100062 A001019
Adjacent sequences: A120994 A120995 A120996 * A120998 A120999 A121000
Wolfdieter Lang, Aug 16 2006