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A157936
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Numbers n divisible by the least prime >= sqrt(n).
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5
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2, 4, 6, 9, 10, 15, 20, 25, 28, 35, 42, 49, 55, 66, 77, 88, 99, 110, 121, 130, 143, 156, 169, 170, 187, 204, 221, 238, 255, 272, 289, 304, 323, 342, 361, 368, 391, 414, 437, 460, 483, 506, 529, 551, 580, 609, 638, 667, 696, 725, 754, 783, 812, 841, 868, 899, 930
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OFFSET
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1,1
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COMMENTS
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Contains A001248, A006094 and A157937 as subsequences.
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LINKS
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Table of n, a(n) for n=1..57.
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FORMULA
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A157936 = A157937 union A001248
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MATHEMATICA
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dQ[n_]:=Module[{srn=Sqrt[n], x}, x=If [PrimeQ[srn], srn, NextPrime[srn]]; Divisible[n, x]]; Select [Range[1000], dQ] (* From Harvey P. Dale, Mar 12 2011 *)
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PROG
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(PARI) for( n=1, 1999, n % nextprime(sqrtint(n-1)+1) | print1(n", ")) /* sqrtint(n-1)+1 avoids rounding errors but can be replaced by sqrt(n) for small n */
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CROSSREFS
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Cf. A157942.
Sequence in context: A065387 A219787 A065388 * A184978 A024978 A191194
Adjacent sequences: A157933 A157934 A157935 * A157937 A157938 A157939
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KEYWORD
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nonn
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AUTHOR
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M. F. Hasler, Mar 10 2009
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STATUS
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approved
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