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Binomial coefficients

I need assistance proving that:

nC0*nC1 + nC1*nC2 + nC2*nC3 + ... +
nC(n-1)*nCn
is equal to:
(n/(n+1)) * ((2n) C n).

I tried Vandermonde's identity but that doesn't seem to work and I can't thing of anything else vaguely relevant.
Does induction work ?
Original post by Math12345
Does induction work ?


Doesn't seem to as there's no easy way to relate nCr and (n+1)cR.

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