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A096932
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Smallest number having exactly s divisors, where s is the n-th semiprime (A001358).
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12
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6, 12, 36, 48, 192, 144, 576, 3072, 1296, 12288, 9216, 196608, 5184, 786432, 36864, 12582912, 46656, 589824, 82944, 2359296, 805306368, 3221225472, 331776, 37748736, 206158430208, 746496, 3298534883328, 5308416, 13194139533312, 2415919104, 2985984, 9663676416
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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a(p*q) = 2^(q-1) * 3^(p-1) for primes p <= q.
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MATHEMATICA
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s[n_] := Module[{f = FactorInteger[n], p, q}, If[Total[f[[;; , 2]]] == 2, p=f[[1, 1]]; q = n/p; 2^(q-1) * 3^(p-1) , Nothing]]; Array[s, 100] (* Amiram Eldar, Apr 13 2024 *)
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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