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%I #15 Nov 10 2012 14:34:03
%S 1,2,3,4,6,8,9,11,12,17,18,22,23,24,29,30,36,37,41,47,48,53,59,60,67,
%T 71,72,79,83,89,97,101,107,113,120,127,131,137,144,149,157,163,167,
%U 173,179,180,191,197,210,211,223,227,233,239,240,251,257,263,269,277
%N Integers not in A218852.
%C Conjecture: This sequence is infinite.
%o (JavaScript)
%o function divisorSum(n) {
%o c=0;
%o for (i=1;i<=n;i++) if (n%i==0) c+=i;
%o return c;
%o }
%o ds=new Array();
%o for (j=1;j<1001;j++) ds[j]=divisorSum(j);
%o a=new Array();
%o ac=0;
%o for (j=1;j<300;j++)
%o for (k=1;k<=j;k++)
%o for (m=1;m<=k;m++)
%o if (ds[j]+ds[k]+ds[m]==ds[j+k+m]) a[ac++]=j+k+m;
%o a.sort(function(a, b) {return a-b;});
%o i=0;
%o while(i++<a.length-1)
%o if (a[i]==a[i+1]) a.splice(i--,1);
%o document.writeln(a);
%o b=new Array();
%o ac=0;
%o bc=0;
%o for (i=0;i<a[a.length-1];i++) if (a[ac]!=i) b[bc++]=i; else ac++;
%o document.writeln(b);
%Y Cf. A218852.
%K nonn
%O 1,2
%A _Jon Perry_, Nov 08 2012