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A367466
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Sum of the final digits of the divisors of n.
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2
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1, 3, 4, 7, 6, 12, 8, 15, 13, 8, 2, 18, 4, 14, 14, 21, 8, 29, 10, 12, 12, 6, 4, 30, 11, 12, 20, 26, 10, 22, 2, 23, 8, 14, 18, 41, 8, 20, 16, 20, 2, 26, 4, 14, 28, 12, 8, 44, 17, 13, 12, 18, 4, 40, 12, 40, 20, 20, 10, 28, 2, 6, 24, 27, 14, 24, 8, 26, 16, 24, 2, 55, 4
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OFFSET
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1,2
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COMMENTS
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First differs from A093811 at a(21) = 12.
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LINKS
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FORMULA
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a(n) = Sum_{d|n} (d mod 10).
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EXAMPLE
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a(21) = 12; The divisors of 21 are {1, 3, 7, 21} and the sum of the final digits of the divisors is 1 + 3 + 7 + 1 = 12.
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MAPLE
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f:= proc(n) add(t mod 10, t = numtheory:-divisors(n)) end proc:
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MATHEMATICA
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Table[DivisorSum[n, Mod[#, 10] &], {n, 100}]
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PROG
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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