A121001 Denominators of partial sums of Catalan numbers scaled by powers of 1/18^2 = 1/324.
1, 324, 52488, 34012224, 5509980288, 595077871104, 96402615118848, 124937789194027008, 60719765548297125888, 19673204037648268787712, 3187059054099019543609344, 2065214267056164664258854912
Offset: 0
Examples
Rationals r(n): [1, 325/324, 52651/52488, 34117853/34012224, 5527092193/5509980288, 596925956851/595077871104, ...].
Formula
a(n)=denominator(r(n)) with r(n) := rI(p=3,n) = sum(C(k)/L(6)^(2*k),k=0..n), with Lucas L(6)=18 and C(k):=A000108(k) (Catalan). The rationals r(n) are given in lowest terms.
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