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Numbers n such that S(n) = 3n (see A068119).
1

%I #9 Jul 29 2013 03:48:22

%S 1,2,10,18,20,25,26,43,46,55,56,71,79,104,107,111,112,113,123,133,136,

%T 140,142,144,145,147,150,155,165,195,196,200,204,206,210,214,216,253,

%U 254,259,260,264,267,327,335,343,360,363,375,376,380,387,388,393

%N Numbers n such that S(n) = 3n (see A068119).

%t ce[n_] := Length[NestWhileList[#*Ceiling[#] &, n + 1/4, ! IntegerQ[#] &]] - 1; nn = Range[395]; t = Accumulate[ce /@ nn]; Select[nn, t[[#]] == 3*# &] (* _Jayanta Basu_, Jul 29 2013 *)

%K nonn

%O 1,2

%A _Benoit Cloitre_, Aug 30 2002