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A366666
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Sum of the divisors of 9^n+1.
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12
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3, 18, 126, 1332, 10476, 109926, 816732, 8906760, 64570086, 706911048, 5357742012, 56496274632, 456919958880, 4661686010664, 35152280388792, 388532214509688, 2779530283277766, 30018958465575240, 230668806145962744, 2431533550553980488, 19410628990783168944
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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(2)=126 because 9^2+1 has divisors {1, 2, 41, 82}.
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MAPLE
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a:=n->numtheory[sigma](9^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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