BetaRegularized[Subscript[z, 1], Subscript[z, 2], a, b] == (1/(a + b)) (a BetaRegularized[Subscript[z, 1], Subscript[z, 2], a + 1, b] + b BetaRegularized[Subscript[z, 1], Subscript[z, 2], a, b + 1])

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2001-10-29