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A341594
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Number of strictly superior odd divisors of n.
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29
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0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 0, 1, 1, 1, 1, 2, 1, 1, 0, 1, 1, 2, 1, 1, 1, 1, 0, 2, 1, 2, 1, 1, 1, 2, 0, 1, 2, 1, 1, 3, 1, 1, 0, 1, 1, 2, 1, 1, 2, 2, 0, 2, 1, 1, 1, 1, 1, 3, 0, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 2, 2, 1, 0, 2, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 0, 1, 1, 3, 1, 1, 2, 1, 1, 4
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OFFSET
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1,15
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COMMENTS
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We define a divisor d|n to be strictly superior if d > n/d. Strictly superior divisors are counted by A056924 and listed by A341673.
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LINKS
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EXAMPLE
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The a(n) divisors for n = 3, 15, 45, 105, 315, 405, 945, 1575, 1890:
3 5 9 15 21 27 35 45 45
15 15 21 35 45 45 63 63
45 35 45 81 63 75 105
105 63 135 105 105 135
105 405 135 175 189
315 189 225 315
315 315 945
945 525
1575
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MATHEMATICA
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Table[Length[Select[Divisors[n], OddQ[#]&&#>n/#&]], {n, 100}]
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PROG
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CROSSREFS
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On odd indices, equals A056924 (number of strictly superior divisors).
Positions of nonzero terms are A116883.
The strictly inferior version is A333805.
The version for squarefree instead of odd divisors is A341595.
The version for prime instead of odd divisors is A341642.
The version for prime-power instead of odd divisors is A341644.
A033676 selects the greatest inferior divisor.
A033677 selects the smallest superior divisor.
A038548 counts superior (or inferior) divisors.
A140271 selects the smallest strictly superior divisor.
A341673 lists strictly superior divisors.
Cf. A000005, A000203, A000265, A001222, A001248, A005408, A006530, A020639, A027193, A058695, A340101.
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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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