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Search: id:A064022
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%I A064022
%S A064022 1,88,369,666,579,1899,789,2688,999,3588,0,4668,0,3789,4599,4689,0,
%T A064022 4789,0,5788,6778,0,0,5889,35559,0,25599,35667,0,35578,0,8888,0,0,
%U A064022 45577,25889,0,0,0,145688,0,45579,0,0,55569,0,0,35888,55677,245559,0,0
%N A064022 Smallest value of m such that prod(m)=n*l(m)*sum(m) where prod(m) is 
               the product of the digits of m, l(m) is the number of digits of m, 
               sum(m) is the sum of the digits of m; or 0 if no such m exists.
%C A064022 If n is divisible by a prime larger than 7, then n can't divide prod(m), 
               so a(n)=0. Are there any other values of n with a(n)=0?
%e A064022 a(2)=88 because prod(88)=64, sum(88)=16, l(88)=2, n=2 and 64=2*2*16
%t A064022 id := IntegerDigits; prod[n_] := Times@@id[n]; l[n_] := Length[id[n]]; 
               sum[n_] := Plus@@id[n]; a[n_] := If[FactorInteger[2n][[ -1, 1]]>7, 
               0, For[m=1, True, m++, If[prod[m]==n*l[m]sum[m], Return[m]]]]
%Y A064022 Cf. A064023.
%Y A064022 Sequence in context: A046330 A001347 A003782 this_sequence A116065 A052049 
               A046378
%Y A064022 Adjacent sequences: A064019 A064020 A064021 this_sequence A064023 A064024 
               A064025
%K A064022 nonn,base
%O A064022 1,2
%A A064022 Felice Russo (felice.russo(AT)katamail.com), Sep 18 2001
%E A064022 Corrected by Larry Reeves (larryr(AT)acm.org), Sep 20 2001
%E A064022 Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Jun 02 2002

    
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Last modified December 15 00:47 EST 2009. Contains 170825 sequences.


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