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A366638
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Sum of the divisors of 7^n+1.
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10
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3, 15, 93, 660, 3606, 34560, 236964, 1559520, 9155916, 77423280, 530807472, 3868683120, 21224771760, 185094572580, 1261494915594, 9988783073280, 49990612274316, 436182213726030, 3279858902194056, 21372989348391720, 122709716651985624, 1082323574100172800
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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a(4)=3606 because 7^4+1 has divisors {1, 2, 1201, 2402}.
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MAPLE
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a:=n->numtheory[sigma](7^n+1):
seq(a(n), n=0..100);
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MATHEMATICA
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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