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A066464
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Least number k such that k has n anti-divisors.
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2
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1, 3, 5, 7, 13, 17, 32, 38, 85, 67, 162, 137, 338, 203, 760, 247, 1225, 472, 578, 682, 1012, 787, 9112, 1463, 2048, 2047, 2888, 2363, 5513, 3465, 5512, 6682, 8978, 5197, 17672, 5198, 71442, 9653, 29768, 8662, 40898, 13513, 81608, 15593, 131072, 35437
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OFFSET
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0,2
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COMMENTS
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See A066272 for definition of anti-divisor.
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LINKS
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MATHEMATICA
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antid[n_] := Select[ Union[ Join[ Select[ Divisors[2n - 1], OddQ[ # ] && # != 1 & ], Select[ Divisors[2n + 1], OddQ[ # ] && # != 1 & ], 2n/Select[ Divisors[ 2*n], OddQ[ # ] && # != 1 &]]] }, # < n & ]]; a = Table[0, {50} ]; Do[ b = Length[ antid[n]]; If[ a[[b + 1]] == 0 && b < 50, a[[b + 1]] = n], {n, 1, 2^17} ]; a
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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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