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Search: id:A072228
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%I A072228
%S A072228 6,244,285,133857,141635817
%N A072228 Numbers n such that n = the sum of the reverses of the proper divisors 
               of n.
%C A072228 I call these numbers "anti-perfect" (compare with the picture-perfect 
               numbers A069942). These are all the anti-perfect numbers up to 3 
               * 10^6.
%C A072228 Next term is greater than 300000000. - Farideh Firoozbakht (mymontain(AT)yahoo.com), 
               Dec 23 2004
%e A072228 The proper divisors of 285 are 1, 3, 5, 15, 19, 57, 95, with sum of reverses 
               = 1 + 3 + 5 + 51 + 91 + 75 + 59 =285. Therefore 285 is anti-perfect.
%t A072228 f[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Do[ If[n == Apply[Plus, 
               Map[f, Drop[Divisors[n], -1]]], Print[n]], {n, 2, 10^7}]
%Y A072228 Cf. A069942, A101701.
%Y A072228 Sequence in context: A064382 A080358 A156936 this_sequence A056238 A041853 
               A113900
%Y A072228 Adjacent sequences: A072225 A072226 A072227 this_sequence A072229 A072230 
               A072231
%K A072228 base,more,nonn,nice
%O A072228 1,1
%A A072228 Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jul 05 2002
%E A072228 One more term from Farideh Firoozbakht (mymontain(AT)yahoo.com), Dec 
               23 2004

    
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Last modified December 9 18:50 EST 2009. Contains 170568 sequences.


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