Beta[z, a, b] == (Pochhammer[a + b, n]/Pochhammer[a, n]) Beta[z, a + n, b] + ((z^(a - 1) (1 - z)^b)/(a + b - 1)) Sum[(Pochhammer[a + b - 1, k]/Pochhammer[a, k]) z^k, {k, 1, n}] /; Element[n, Integers] && n >= 0

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2001-10-29