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A264165
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3-smooth numbers whose number of divisors is 3-smooth.
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2
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1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 27, 32, 36, 54, 72, 96, 108, 128, 216, 243, 256, 288, 384, 486, 768, 864, 972, 1152, 1944, 2048, 2187, 2304, 3456, 4374, 6144, 6561, 6912, 7776, 8748, 13122, 17496, 18432, 26244, 31104, 32768, 52488, 55296, 62208, 69984
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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MATHEMATICA
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smQ[n_] := n == Times @@ ({2, 3}^IntegerExponent[n, {2, 3}]);
seq[max_] := Sort@ Flatten@ Table[2^i * 3^j, {i, Select[Range[0, Floor[Log2[max]]], smQ[# + 1] &]}, {j, Select[Range[0, Floor[Log[3, max/2^i]]], smQ[# + 1] &]}]; seq[70000] (* Amiram Eldar, Sep 03 2023 *)
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PROG
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(Haskell)
a264165 n = a264165_list !! (n-1)
a264165_list = filter ((== 1) . a065333 . a000005') a003586_list
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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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