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A046871
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Sigma[ 2,n ] divides Sigma[ 4,n ].
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3
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1, 4, 9, 16, 20, 25, 36, 48, 49, 64, 81, 100, 121, 144, 162, 169, 180, 196, 225, 245, 256, 289, 324, 361, 400, 432, 441, 484, 500, 529, 576, 605, 625, 648, 676, 729, 784, 841, 900, 931, 961, 980, 1024, 1089, 1156, 1200, 1225, 1280, 1296, 1369, 1444, 1521
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OFFSET
| 1,2
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COMMENTS
| sigma_2(n) is the sum of the squares of the divisors of n (A001157).
/sigma_4(n) is the sum of the 4th powers of the divisors of n (A001159).
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EXAMPLE
| n=a[ 8 ]=48 of which divisor power sums for k=0,1,2,3,4 are 10,124,3410,131068, 5732210 resp. Here Sigma_2=3410 and Sigma_4=3410*1681.
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CROSSREFS
| A020487, A020486, A046841.
Sequence in context: A010401 A066213 A010441 * A020487 A046870 A127702
Adjacent sequences: A046868 A046869 A046870 * A046872 A046873 A046874
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu)
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