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A109941
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Sum of all n-digit multiples of n.
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2
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45, 2430, 165150, 12370500, 989955000, 82499850000, 7071428928571, 618749955000000, 55000000350000000, 4949999995500000000, 449999999955000000000, 41250000000150000000000, 3807692307689192307692307, 353571428571466428571428572, 32999999999999850000000000000
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2) = 2430, a(2) = 10 +12+...+96+98 = 45*(10+98)/2.
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MATHEMATICA
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Table[Sum[i, {i, n*Ceiling[(10^(n - 1))/n], 10^n - 1, n}], {n, 15}] (* Hans Havermann *)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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