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A250215 Least k such that the n-th weak irregular prime (A250216(n)) divides A241601(k). 0
11, 23, 32, 13, 15, 44, 7, 27, 29, 19, 63, 24, 22, 43, 129, 130, 62, 75, 133, 84, 211, 127, 164, 100, 84, 9, 20, 156, 88, 87, 280, 19, 71, 125, 163, 100, 200, 382, 126, 159, 240, 215, 196, 130, 94, 292, 141, 400, 86, 270, 222, 175, 389, 52, 45, 22, 592, 522, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A prime p can divide A241601(k) for more than one k; the first few examples are as follows:
p k
67 27, 58
101 63, 68
149 130, 147
157 62, 110
241 211, 239
263 100, 213
307 88, 91, 137
311 87, 193, 292
349 19, 257
353 71, 186, 300
etc.
LINKS
Eric Weisstein's World of Mathematics, Irregular Pair
EXAMPLE
19 is the first weak irregular prime and divides A241601(11) = 50521, so a(1) = 11.
CROSSREFS
Sequence in context: A344175 A126330 A090506 * A208326 A097657 A041234
KEYWORD
nonn
AUTHOR
Eric Chen, Dec 26 2014
EXTENSIONS
More terms from Jinyuan Wang, Feb 18 2022
STATUS
approved

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Last modified March 29 03:51 EDT 2024. Contains 371264 sequences. (Running on oeis4.)