On Mon, 13 Sep 2010 at 10:27AM +0200, Fredrik Johansson wrote:
> This happens because g(25) is a Rational, so mpmath rounds it to a
> floating-point value (with 53-bit precision) upon coercion. Note:
>
> sage: type(g(25))
>
> sage: Integer(Rational(60529607948876437).n(53))
> 60529607948876440
>
On Mon, Sep 13, 2010 at 9:36 AM, Dan Drake wrote:
> I've found something strange with mpmath's hypergeometric functions:
>
> sage: f = lambda n: sum(binomial(n,k)^2 * 2^k for k in range(n+1))
> sage: g = lambda n: (-f(n) + 8*f(n-1) - 3*f(n-2))/8
>
> Now define:
>
> sage: h = lambda n: catalan_numb
