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%I #12 Oct 11 2019 12:36:19
%S 1,2,3,5,10,13,14,16,19,29,30,33,46,60,65,81,82,85,104,114,117,119,
%T 120,123,128,141,144,158,187,217,218,234,267,269,274,277,278,297,310,
%U 320,321,335,336,338,343,389,390,406,407,417,420,433,434,437,442,456,475
%N a(1)=1. For n>=2, a(n) = a(n-1) + (largest divisor of n which occurs among the earlier terms of the sequence).
%H Ivan Neretin, <a href="/A123090/b123090.txt">Table of n, a(n) for n = 1..10000</a>
%e The largest divisor of 9 which occurs among the first 8 terms of the sequence is 3. So a(9) = a(8) + 3 = 19.
%t f[l_List] := Block[{n = Length[l] + 1},Append[l, Last[l] + Max[Select[l, Mod[n, # ] == 0 &]]]];Nest[f, {1}, 60] (* _Ray Chandler_, Sep 30 2006 *)
%K nonn
%O 1,2
%A _Leroy Quet_, Sep 27 2006
%E Extended by _Ray Chandler_, Sep 30 2006