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A158989 Numbers n such that product of double factorials of the digits of n equals sigma(n). 0

%I #2 Mar 30 2012 17:37:48

%S 1,54,62,4190,4920,10538,12376,16065,16732,26345,37236,47026,48323,

%T 53480,56712,58520,61209,62337,65163,83720,84135,94520,100980,126238,

%U 135266,141078,143726,146910,147354,154238,174217,183505,185334,207328

%N Numbers n such that product of double factorials of the digits of n equals sigma(n).

%e sigma(444119)=4!!*4!!*4!!*1!!*1!!*9!!, so 444119 is in the sequence.

%t Select[Range[210000],DivisorSigma[1,# ]==Apply[Times,IntegerDigits[ # ]!! ]&]

%Y Cf. A137603, A158990, A158991, A158992.

%K base,easy,nonn

%O 1,2

%A _Farideh Firoozbakht_, Jul 07 2009

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Last modified March 28 22:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)