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A034660
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Sum of n-th powers of divisors of 12.
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5
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6, 28, 210, 2044, 22386, 257908, 3037530, 36130444, 431733666, 5170140388, 61978939050, 743375541244, 8918294543346, 107006334784468, 1283997101947770, 15407492847694444, 184887084343023426, 2218628050709022148, 26623434909949071690, 319480609006403630044
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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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G.f.: (6 - 140*x + 1148*x^2 - 4200*x^3 + 6888*x^4 - 4032*x^5)/((1-x)*(1-2*x)*(1-3*x)*(1-4*x)*(1-6*x)*(1-12*x)). - Michael Somos, Apr 02 2003
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MATHEMATICA
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a[n_] := Plus@@(Divisors[12]^n)
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PROG
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(PARI) a(n)=if(n<0, 0, polsym((x-1)*(x-2)*(x-3)*(x-4)*(x-6)*(x-12), n)[n+1])
(PARI) a(n)=if(n<0, 0, 1^n+2^n+3^n+4^n+6^n+12^n)
(Magma) [&+[Divisors(12)[i]^n: i in [1..6]]: n in [0..20]]; // Vincenzo Librandi, Apr 17 2014
(Python)
def a(n): return sum(d**n for d in [1, 2, 3, 4, 6, 12])
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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