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A339506 Numbers surviving a repeated sieving process for pseudo-lucky numbers (A249876). 1
1, 3, 5, 7, 13, 17, 31, 35, 41, 43, 47, 63, 101, 105, 107, 131, 175, 177, 185, 211, 235, 237, 267, 301, 305, 315, 323, 397, 407, 451, 571, 631, 633, 683, 757, 841, 877, 947, 987, 1043, 1221, 1251, 1431, 1501, 1655, 1781, 1961, 1981, 2023, 2067, 2157, 2197, 2253, 2367, 2457, 2505, 2615 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Start with the positive integers as the 1st starting sequence. The 1st full sieving process for the pseudo-lucky numbers begins with the 2nd term in the 1st starting sequence and generates A249876 (the 2nd starting sequence). The n-th full sieving process begins with the (n+1)-th term in the n-th starting sequence and generates the (n+1)-th starting sequence. The numbers that are left form the final sequence.
Let b(m) be the number of elements of this sequence <= m. Let c(m) = round(square(s*m/log(s*m))), where s = 11.
--------------------------------
m | b(m) | c(m) | b(m)-c(m)
--------------------------------
10^2 | 12 | 13 | -1
10^3 | 39 | 34 | +5
10^4 | 103 | 97 | +6
5*10^4 | 210 | 204 | +6
6*10^4 | 228 | 222 | +6
7*10^4 | 236 | 238 | -2
8*10^4 | 256 | 254 | +2
9*10^4 | 270 | 268 | +3
10^5 | 282 | 281 | +1
--------------------------------
Is c(m) an approximation to b(m)?
LINKS
EXAMPLE
The 1st full sieving process:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 ...
1 X 3 X 5 X 7 X 9 X 11 X 13 X 15 X 17 X 19 X 21 X 23 X 25 ...
1 3 5 7 X 11 13 15 17 X 21 23 25 ...
1 3 5 7 11 13 X 17 21 23 25 ...
Continuing the above procedure generates the 2nd starting sequence (the pseudo-lucky numbers) to begin the 2nd full sieving process:
1 3 5 7 11 13 17 21 23 25 31 35 41 43 45 47 55 57 63 65 73 75 83 87 95 ...
1 3 5 7 X 13 17 21 23 X 31 35 41 43 X 47 55 57 63 X 73 75 83 87 X ...
1 3 5 7 13 17 X 23 31 35 41 43 47 X 57 63 73 75 83 87 ...
1 3 5 7 13 17 23 31 35 41 43 47 X 63 73 75 83 87 ...
1 3 5 7 13 17 23 31 35 41 43 47 63 73 75 83 X ...
Continuing the above procedure generates the 3rd starting sequence to begin the 3rd full sieving process:
1 3 5 7 13 17 23 31 35 41 43 47 63 73 75 83 101 105 107 123 127 131 151 ...
1 3 5 7 13 17 X 31 35 41 43 47 63 X 75 83 101 105 107 123 X 131 151 ...
1 3 5 7 13 17 31 35 41 43 47 63 X 83 101 105 107 123 131 151 ...
1 3 5 7 13 17 31 35 41 43 47 63 83 101 105 107 X 131 151 ...
Continuing the above procedure generates the 4th starting sequence to begin the 4th full sieving process:
1 3 5 7 13 17 31 35 41 43 47 63 83 101 105 107 131 151 153 175 177 185 ...
1 3 5 7 13 17 31 35 41 43 47 63 X 101 105 107 131 151 153 175 177 185 ...
1 3 5 7 13 17 31 35 41 43 47 63 101 105 107 131 X 153 175 177 185 ...
Continuing the above procedure generates the 5th starting sequence to begin the 5th full sieving process:
1 3 5 7 13 17 31 35 41 43 47 63 101 105 107 131 153 175 177 185 211 235 ...
1 3 5 7 13 17 31 35 41 43 47 63 101 105 107 131 X 175 177 185 211 235 ...
...
Continue forever and the numbers not crossed off give the sequence.
CROSSREFS
Sequence in context: A038929 A242755 A070806 * A178490 A182981 A234388
KEYWORD
nonn
AUTHOR
Lechoslaw Ratajczak, Dec 07 2020
STATUS
approved

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Last modified May 11 23:16 EDT 2024. Contains 372431 sequences. (Running on oeis4.)