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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
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
KEYWORD
nonn
AUTHOR
Eric Chen, Dec 26 2014
EXTENSIONS
More terms from Jinyuan Wang, Feb 18 2022
STATUS
approved