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Numbers whose product of digits equals the number of digits times the sum of digits.
2

%I #28 Sep 10 2018 04:41:30

%S 0,1,2,3,4,5,6,7,8,9,36,44,63,159,167,176,195,235,253,325,333,352,519,

%T 523,532,591,617,671,716,761,915,951,1247,1274,1344,1427,1434,1443,

%U 1472,1724,1742,2147,2174,2226,2262,2417,2471,2622,2714,2741,3144,3414

%N Numbers whose product of digits equals the number of digits times the sum of digits.

%C A subset of A061013.

%H Giovanni Resta, <a href="/A064154/b064154.txt">Table of n, a(n) for n = 1..10000</a> (first 1001 terms from Harry J. Smith)

%e 36 belongs to the sequence because 3*6 = 18 and 2*(3+6) = 18.

%t Select[Range[0, 3414], (d = IntegerDigits[#]; Times @@ d == Length[d] Plus @@ d) &] (* _Giovanni Resta_, Jun 25 2018 *)

%o (PARI) for(n=0,10000,my(v=digits(n));if(vecprod(v)==#v*vecsum(n),print1(n,", "))) \\ _Derek Orr_, Sep 09 2018

%Y Cf. A061013, A316147.

%K easy,nonn,base

%O 1,3

%A _Felice Russo_, Sep 14 2001

%E Offset set to 1 by _Giovanni Resta_, Jun 25 2018