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 A246458 Catalan number analogs for A048804, the generalized binomial coefficients for the radical sequence (A007947). 2
 1, 1, 1, 5, 7, 7, 11, 143, 715, 2431, 4199, 29393, 52003, 37145, 7429, 215441, 392863, 4321493, 7960645, 58908773, 109402007, 407771117, 762354697, 3811773485, 35830670759, 19293438101, 327988447717, 2483341104143, 4709784852685, 17897182440203, 34062379482967 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS 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). LINKS Tom Edgar and Michael Z. Spivey, Multiplicative functions, generalized binomial coefficients, and generalized Catalan numbers, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.6. FORMULA a(n) = A048804(2n,n) / A007947(n+1). EXAMPLE A048804(10,5) = 42 and A007947(6) = 6, so a(5)=42/6=7. PROG (Sage) [(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]] CROSSREFS Cf. A007947, A048804, A048803, A245798, A000108. Sequence in context: A216835 A033932 A144186 * A153979 A126992 A028316 Adjacent sequences:  A246455 A246456 A246457 * A246459 A246460 A246461 KEYWORD nonn AUTHOR Tom Edgar, Aug 26 2014 STATUS approved

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Last modified December 17 14:12 EST 2018. Contains 318201 sequences. (Running on oeis4.)