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A157942
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Numbers n divisible by the largest prime <= sqrt(n), A007917(A000196(n)).
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5
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4, 6, 8, 9, 12, 15, 18, 21, 24, 25, 30, 35, 40, 45, 49, 56, 63, 70, 77, 84, 91, 98, 105, 112, 119, 121, 132, 143, 154, 165, 169, 182, 195, 208, 221, 234, 247, 260, 273, 286, 289, 306, 323, 340, 357, 361, 380, 399, 418, 437, 456, 475, 494, 513, 529, 552, 575, 598
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OFFSET
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1,1
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COMMENTS
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Includes squares of primes (A001248; exactly the cases where we have "=" in the definition) and products of pairs of consecutive primes (A006094) as subsequences.
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LINKS
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MATHEMATICA
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Select[Range[4, 599], IntegerQ[#/Prime[PrimePi[Sqrt[#]]]]&] (* Jayanta Basu, May 03 2013 *)
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PROG
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(PARI) for( n=4, 999, n % precprime(sqrtint(n)) | print1(n", "))
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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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