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%I #12 Oct 12 2024 16:10:24
%S 1,2,4,7,9,12,18,25,27,31,33,37,39,43,45,49,52,64,76,88,100,112,125,
%T 127,129,134,144,167,169,172,187,189,196,214,226,238,252,284,300,331,
%U 333,339,345,354,374,387,394,407,409,411,417,423,430,447,453,459,467,469
%N a(n) = sum of first n terms of sequence A120877.
%H Michael De Vlieger, <a href="/A120878/b120878.txt">Table of n, a(n) for n = 1..10000</a>
%t nn = 120; c[_] := 0; s = a[1] = c[1] = 1; w = {1}; Do[k = Total@ Map[c, Select[w, Divisible[s, #] &]]; s += k; c[k]++; a[n] = s; If[FreeQ[w, k], AppendTo[w, k]], {n, 2, nn}]; Array[a, nn] (* _Michael De Vlieger_, Oct 12 2024 *)
%o (PARI) {m=60;v=[1];for(n=2,m,a=0;q=sum(i=1,n-1,v[i]);for(j=1,n-1,if(q%v[j]==0,a++));print1(q,",");v=concat(v,a))} \\ Klaus Brockhaus, Aug 16 2006
%Y Cf. A120877.
%K nonn
%O 1,2
%A _Leroy Quet_, Jul 10 2006
%E More terms from _Klaus Brockhaus_, Aug 16 2006