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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A246458 Catalan number analogs for A048804, the generalized binomial coefficients for the radical sequence (A007947).

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%I A246458 #14 Jan 25 2016 14:25:04
%S A246458 1,1,1,5,7,7,11,143,715,2431,4199,29393,52003,37145,7429,215441,
%T A246458 392863,4321493,7960645,58908773,109402007,407771117,762354697,
%U A246458 3811773485,35830670759,19293438101,327988447717,2483341104143,4709784852685,17897182440203,34062379482967
%N A246458 Catalan number analogs for A048804, the generalized binomial coefficients for the radical sequence (A007947).
%C A246458 One definition of the Catalan numbers is binomial(2*n,n) / (n+1); the current sequence models this definition using the generalized binomial coefficients arising from the radical sequence (A007947).
%H A246458 Tom Edgar and Michael Z. Spivey, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Edgar/edgar3.html">Multiplicative functions, generalized binomial coefficients, and generalized Catalan numbers</a>, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.6.
%F A246458 a(n) = A048804(2n,n) / A007947(n+1).
%e A246458 A048804(10,5) = 42 and A007947(6) = 6, so a(5)=42/6=7.
%o A246458 (Sage)
%o A246458 [(1/(prod(x for x in prime_divisors(n+1))))*prod(prod(x for x in prime_divisors(i)) for i in [1..2*n])/prod(prod(x for x in prime_divisors(i)) for i in [1..n])^2 for n in [0..100]]
%Y A246458 Cf. A007947, A048804, A048803, A245798, A000108.
%K A246458 nonn
%O A246458 0,4
%A A246458 _Tom Edgar_, Aug 26 2014