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A218980
Integers not in A218852.
2
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, 71, 72, 79, 83, 89, 97, 101, 107, 113, 120, 127, 131, 137, 144, 149, 157, 163, 167, 173, 179, 180, 191, 197, 210, 211, 223, 227, 233, 239, 240, 251, 257, 263, 269, 277
OFFSET
1,2
COMMENTS
Conjecture: This sequence is infinite.
PROG
(JavaScript)
function divisorSum(n) {
c=0;
for (i=1; i<=n; i++) if (n%i==0) c+=i;
return c;
}
ds=new Array();
for (j=1; j<1001; j++) ds[j]=divisorSum(j);
a=new Array();
ac=0;
for (j=1; j<300; j++)
for (k=1; k<=j; k++)
for (m=1; m<=k; m++)
if (ds[j]+ds[k]+ds[m]==ds[j+k+m]) a[ac++]=j+k+m;
a.sort(function(a, b) {return a-b; });
i=0;
while(i++<a.length-1)
if (a[i]==a[i+1]) a.splice(i--, 1);
document.writeln(a);
b=new Array();
ac=0;
bc=0;
for (i=0; i<a[a.length-1]; i++) if (a[ac]!=i) b[bc++]=i; else ac++;
document.writeln(b);
CROSSREFS
Cf. A218852.
Sequence in context: A002479 A010458 A354620 * A084829 A018649 A341159
KEYWORD
nonn
AUTHOR
Jon Perry, Nov 08 2012
STATUS
approved