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 A095411 Numbers n such that total number of decimal digits of all distinct prime factors of n is smaller than the number of digits of n. 2

%I #5 Oct 15 2013 22:32:25

%S 6,22,26,30,33,34,38,39,42,44,46,51,52,55,57,58,60,62,65,66,68,69,70,

%T 74,76,77,78,82,84,85,86,87,88,90,91,92,93,94,95,99,102,110,114,130,

%U 132,138,143,154,156,165,170,174,182,186,187,190,195,198,202,204,206,209

%N Numbers n such that total number of decimal digits of all distinct prime factors of n is smaller than the number of digits of n.

%F Solutions to A095407[x] < A055642[x].

%e n=55: 2 digits, prime set={5,11} with {5,1,1} digits, 3>2, 55 is here.

%t ffi[x_] :=Flatten[FactorInteger[x]] lf[x_] :=Length[FactorInteger[x]] ba[x_] :=Table[Part[ffi[x], 2*j-1], {j, 1, lf[x]}] tdp[x_] :=Flatten[Table[IntegerDigits[Part[ba[x], j]], {j, 1, lf[x]}], 1] pl[x_] :=Length[tdp[x]] nl[x_] :=Length[IntegerDigits[x]] t1=Table[nl[w], {w, 1, 1000}];t2=Table[pl[w], {w, 1, 1000}];t2-t1 Flatten[Position[t2-t1, 1]]

%Y Cf. A055642, A095407, A095408, A095409, A095410.

%K base,nonn

%O 1,1

%A _Labos Elemer_, Jun 21 2004

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Last modified April 20 10:35 EDT 2024. Contains 371827 sequences. (Running on oeis4.)