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%I #11 Nov 03 2019 22:34:25
%S 0,1,1,1,1,2,1,1,1,2,2,2,2,2,2,1,2,2,2,2,2,3,2,2,1,3,1,2,2,3,2,1,3,3,
%T 2,2,2,3,3,2,2,3,2,3,2,3,2,2,1,2,3,3,2,2,3,2,3,3,2,3,2,3,2,1,3,4,2,3,
%U 3,3,2,2,2,3,2,3,3,4,2,2,1,3,2,3,3,3,3,3,2,3,3,3,3,3,3,2,2,2,3,2,3,4,3,3,3
%N Total number of decimal digits of all distinct prime factors of n.
%C a(n) <= A055642(n) + A001221(n) - 1 since the product of a k digit number and an m digit number has at least k+m-1 digits. - _Chai Wah Wu_, Nov 03 2019
%H Charles R Greathouse IV, <a href="/A095407/b095407.txt">Table of n, a(n) for n = 1..10000</a>
%e n=22: prime set={2,11}, a[22]=1+2=3.
%t Prepend[(Total [ Length[IntegerDigits[#]] & /@ ( #[[1]] & /@ FactorInteger[#])] & /@ Range[2, 105]), 0] (* _Zak Seidov_, Aug 26 2016 *)
%o (PARI) a(n)=vecsum(apply(p->#Str(p), factor(n)[,1])) \\ _Charles R Greathouse IV_, Aug 26 2016
%Y Cf. A055642, A001221.
%K base,nonn
%O 1,6
%A _Labos Elemer_, Jun 21 2004
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