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A180851
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Sum of divisors as increasing powers.
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3
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1, 5, 10, 69, 26, 1328, 50, 4165, 739, 10130, 122, 2994048, 170, 38764, 50760, 1052741, 290, 34072601, 362, 64100694, 194834, 235592, 530, 110111416192, 15651, 459178, 532180, 482430598, 842, 656271867808, 962, 1074794565, 1187262
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OFFSET
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1,2
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LINKS
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EXAMPLE
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For n=4, the divisors of 4 are [1, 2, 4] and summing them as increasing powers yields: 1^1+2^2+4^3 = 69.
For n=12, the divisors of 12 are [1, 2, 3, 4, 6, 12] and summing them as increasing powers yields: 1^1+2^2+3^3+4^4+6^5+12^6 = 2994048.
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MAPLE
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f:= proc(n) local D, k;
D:=sort(convert(numtheory:-divisors(n), list));
add(D[k]^k, k=1..nops(D))
end proc:
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MATHEMATICA
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Total[Divisors[#]^Range[DivisorSigma[0, #]]]&/@Range[40] (* Harvey P. Dale, Aug 16 2011 *)
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PROG
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(PARI) a(n) = my(d = divisors(n)); sum(k=1, #d, d[k]^k); \\ Michel Marcus, Jan 01 2016
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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