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A099204
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A variation on Flavius's sieve (A000960): Start with the natural numbers; at the k-th sieving step, remove every p-th term of the sequence remaining after the (k-1)-st sieving step, where p is the k-th prime; iterate.
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5
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1, 3, 7, 9, 15, 19, 25, 31, 33, 37, 45, 51, 61, 63, 67, 69, 81, 85, 97, 105, 109, 111, 123, 129, 135, 141, 145, 151, 159, 169, 183, 189, 195, 201, 211, 213, 219, 225, 229, 241, 261, 265, 273, 277, 289, 291, 307, 315, 319, 321, 325, 339, 351, 355, 361, 375, 381
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Index entries for sequences generated by sieves
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EXAMPLE
| Start with
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ... and delete every second term, giving
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 ... and delete every 3rd term, giving
1 3 7 9 13 15 19 21 25 27 ... and delete every 5th term, giving
1 3 7 9 15 19 21 25 ... and delete every 7th term, giving
.... Continue for ever and what's left is the sequence.
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MAPLE
| S[1]:={seq(i, i=1..390)}: for n from 2 to 390 do S[n]:=S[n-1] minus {seq(S[n-1][ithprime(n-1)*i], i=1..nops(S[n-1])/ithprime(n-1))} od: S[390]; - Emeric Deutsch (deutsch(AT)duke.poly.edu), Nov 17 2004
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MATHEMATICA
| Clear[l, ps]; ps=Prime[Range[100]]; l=Range[400]; Do[l=Drop[l, {First[ps], -1, First[ps]}]; ps=Rest[ps], {17}]; l (* From Harvey P. Dale, Sep 03 2011 *)
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CROSSREFS
| Cf. A000960, A099207, A099243.
Sequence in context: A197625 A190811 A104177 * A070993 A191131 A128539
Adjacent sequences: A099201 A099202 A099203 * A099205 A099206 A099207
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Nov 16 2004
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EXTENSIONS
| More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Nov 16 2004
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