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A246466 Catalan number analogs for A246465, the generalized binomial coefficients for A003557.

%I A246466 #9 Jan 25 2016 14:24:36
%S A246466 1,1,2,1,2,6,12,3,2,2,4,2,4,20,360,45,90,30,60,30,60,60,120,90,36,252,
%T A246466 56,28,56,56,112,7,42,42,84,14,28,28,280,70,140,3780,7560,3780,2520,
%U A246466 2520,5040,630,180,36,216,108,216,24,48,12,24,24,48,72,144,1584
%N A246466 Catalan number analogs for A246465, the generalized binomial coefficients for A003557.
%C A246466 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 sequence (A003557), which is n/rad(n).
%H A246466 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 A246466 a(n) = A246465(2n,n) / A003557(n+1).
%e A246466 A246465(14,7) = 12 and A003557(8) = 4, so a(7)=12/4=3.
%o A246466 (Sage)
%o A246466 D=[0]+[n/prod([x for x in prime_divisors(n)]) for n in [1..122]]
%o A246466 T=[[prod(D[1:m+1])/(prod(D[1:n+1])*prod(D[1:(m-n)+1])) for n in [0..m]] for m in [0..len(D)-1]]
%o A246466 [(1/D[i+1])*T[2*i][i] for i in [0..61]]
%Y A246466 Cf. A003557, A246465, A245798, A000108, A007947, A246458.
%K A246466 nonn
%O A246466 0,3
%A A246466 _Tom Edgar_, Aug 27 2014