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A049030
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Sum of sigma(j) for 1<=j<10^n, where sigma(j) = A048050(j) is the sum of the proper divisors >1 of j (excluding 1 and n).
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0
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OFFSET
| 1,1
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LINKS
| C. Rivera, Prime Puzzles and Problems Connection
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FORMULA
| At a(3)=320243, for example, take a(3) from A049000: 820741-500498=320243. Compute 500498 from 999*1000/2=499500, split evenly and reverse to 500499-1=500498. Add a 9 and 0 for each successive term.
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EXAMPLE
| For n=1, the sum of sigma(j), for j<10 is 0+0+0+2+0+5+0+6+3=16, so a(1)=16.
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CROSSREFS
| Cf. A001065, A048050, A048995.
Sequence in context: A016876 A123282 A091160 * A051551 A003773 A087519
Adjacent sequences: A049027 A049028 A049029 * A049031 A049032 A049033
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KEYWORD
| base,nonn
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AUTHOR
| Enoch Haga and Jud McCranie (Enokh(AT)comcast.net and JudMcCranie(AT)ugaalum.uga.edu)
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