%I A139542
%S A139542 1,2,3,4,6,8,10,12,15,18,21,24,28,32,36,42,48,54,60,66,72,80,88,96,104,
%T A139542 112,120,130,140,150,160,170,180,192,204,216,228,240,255,270,285,300,
%U A139542 315,330,345,360,378,396,414,432,450,468,486,504,525,546,567,588,609
%N A139542 a(n) = a(n-1) + largest divisor of a(n-1) <= sqrt(a(n-1)).
%e A139542 Term after 36 is 42 because largest divisor of 36 <= sqrt(36) is 6 and 
               36+6=42
%t A139542 a = {1}; Do[AppendTo[a, a[[ -1]] + Max[Select[Divisors[a[[ -1]]], # <= 
               Sqrt[a[[ -1]]] &]]], {60}]; a [From Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), 
               Aug 28 2008]
%Y A139542 Sequence in context: A130519 A001972 A005705 this_sequence A093717 A002093 
               A067069
%Y A139542 Adjacent sequences: A139539 A139540 A139541 this_sequence A139543 A139544 
               A139545
%K A139542 nonn
%O A139542 1,2
%A A139542 J. Lowell (jhbubby(AT)mindspring.com), Jun 10 2008
%E A139542 More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), 
               Aug 28 2008