A158989 Numbers n such that product of double factorials of the digits of n equals sigma(n).
1, 54, 62, 4190, 4920, 10538, 12376, 16065, 16732, 26345, 37236, 47026, 48323, 53480, 56712, 58520, 61209, 62337, 65163, 83720, 84135, 94520, 100980, 126238, 135266, 141078, 143726, 146910, 147354, 154238, 174217, 183505, 185334, 207328
Offset: 1
Examples
sigma(444119)=4!!*4!!*4!!*1!!*1!!*9!!, so 444119 is in the sequence.
Programs
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Mathematica
Select[Range[210000],DivisorSigma[1,# ]==Apply[Times,IntegerDigits[ # ]!! ]&]