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A056533 Even sieve: start with natural numbers, remove every 2nd term, remove every 4th term from what remains, remove every 6th term from what remains, etc. 2
1, 3, 5, 9, 11, 17, 19, 25, 27, 35, 37, 43, 51, 57, 59, 69, 75, 83, 85, 97, 101, 113, 117, 129, 131, 147, 153, 161, 163, 181, 185, 195, 203, 211, 219, 233, 243, 257, 259, 273, 275, 291, 307, 315, 321, 339, 341, 357, 369, 387, 389, 401, 417, 425, 437, 453, 465 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..57.

Index entries for sequences generated by sieves

EXAMPLE

Start with (1,2,3,4,5,6,7,8,9,10,11,12,....), remove every 2nd term to get (1,3,5,7,9,11,...), remove every 4th term to get (1,3,5,9,11,...), etc.

MATHEMATICA

lst = Range@480; i = 2; While[i <= (len = Length[lst]), lst = Drop[lst, {i, len, i}]; i+=2]; lst (* Robert G. Wilson v, May 26 2006 *)

CROSSREFS

After k-th round of sieve, A001147(k)/A000165(k) of natural numbers remain, declining slowly to zero.

Sequence in context: A118113 A258165 A076193 * A329110 A114186 A117992

Adjacent sequences:  A056530 A056531 A056532 * A056534 A056535 A056536

KEYWORD

nonn

AUTHOR

Henry Bottomley, Jun 19 2000

STATUS

approved

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Last modified December 13 12:37 EST 2019. Contains 329968 sequences. (Running on oeis4.)