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 A228893 Numbers n such that the concatenation of the frequency of each decimal digit of n is divisible by n. 0
 1, 2, 4, 5, 10, 14, 20, 25, 32, 40, 50, 52, 73, 100, 112, 120, 125, 150, 152, 188, 200, 226, 240, 250, 300, 305, 320, 335, 400, 420, 500, 600, 674, 700, 1000, 1100, 1144, 1210, 1250, 1430, 2000, 2020, 2500, 2660, 3250, 4000, 4015, 5000, 5500, 6500, 8629, 10000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Start with any number n and denote(f0, f1,...,f9) the number of the digits 0, 1, 2,..., 9 of n. The sequence lists the numbers n such that m = f0f1f2f3f4f5f6f7f8f9/n is an integer. The corresponding m are: 100000000, 5000000, 25000, 2000, 110000000, 7150000, 50500000, 400400, 343750, 25002500, 20000200, 192500, 13700, 21000000, 1875000, 9250000, 880080, 7333400, 723750, 531915,... LINKS EXAMPLE 226 is in the sequence because the table of the frequencies is: frequency of 0 = 0; frequency of 1 = 0; frequency of 2 = 2; frequency of 3 = 0; frequency of 4 = 0; frequency of 5 = 0; frequency of 6 = 1; frequency of 7 = 0; frequency of 8 = 0; frequency of 9 = 0. The concatenation of the frequencies is 20001000, and 20001000/226 = 88500. MAPLE with(numtheory): T:=array(0..9):   for n from 1 to 200000 do:      x:=convert(n, base, 10):n1:=nops(x):(1..n1):        for k from 0 to 9 do:           T[k]:=0:od:jj:=0:             for i from 0 to 9 do:               for j from 1 to n1 do:                 if x[j]=i                 then                 T[i]:=T[i]+1:jj:=jj+1:                 else                 fi:               od:             od:                s:= sum('T[9-i]*10^i', 'i'=0..9):s1:=s/n:                if floor(s1)=s1                then                printf(`%d, `, n):                else                fi:        od: CROSSREFS Sequence in context: A002237 A329136 A067935 * A272622 A097133 A023165 Adjacent sequences:  A228890 A228891 A228892 * A228894 A228895 A228896 KEYWORD nonn,base,less AUTHOR Michel Lagneau, Sep 07 2013 STATUS approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)