A056533 - OEIS

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.

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.