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A332801
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a(n) is the number of even results of n mod k, for 1 < k < n.
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1
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0, 0, 0, 1, 1, 3, 1, 4, 3, 5, 3, 7, 3, 9, 5, 8, 6, 11, 5, 13, 7, 13, 7, 15, 8, 16, 10, 16, 10, 20, 8, 21, 11, 21, 13, 22, 12, 24, 14, 24, 14, 28, 12, 30, 16, 28, 16, 30, 17, 32, 18, 32, 18, 36, 18, 36, 20, 36, 20, 40, 18, 42, 22, 39, 25, 41, 23, 43, 25, 45, 23, 48, 22, 50
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OFFSET
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1,6
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LINKS
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EXAMPLE
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n(7) = 1 because only 7 mod 5 = 2 is even.
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MATHEMATICA
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Table[Total[Boole[EvenQ/@Mod[n, Range[2, n-1]]]], {n, 80}] (* Harvey P. Dale, Aug 09 2021 *)
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PROG
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(PARI) a(n) = sum(k=2, n-1, ((n % k) % 2)== 0); \\ Michel Marcus, Feb 24 2020
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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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