Derivative[m, 0][BesselI][\[Nu], z] == Sum[(1/k!) (z/2)^(2 k) D[(1/Gamma[k + \[Nu] + 1]) (z/2)^\[Nu], {\[Nu], m}], {k, 0, Infinity}] /; Element[m, Integers] && m >= 0

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2001-10-29