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A105457
Number of irregular primes less than e^n.
2
0, 0, 0, 1, 6, 21, 66, 170, 404, 984, 2384, 5877, 14459, 36720, 92657, 234376, 597082, 1525209, 3913689, 10076194, 26016985
OFFSET
1,5
MATHEMATICA
ip={ the list of irregular primes to 12 million }; Table[ Length[ Select[ip, # < E^n &]], {n, 16}]
CROSSREFS
KEYWORD
hard,nonn,more
AUTHOR
Robert G. Wilson v, Apr 07 2005
EXTENSIONS
a(16) corrected and a(17)-a(21) added by Amiram Eldar, Mar 05 2019
STATUS
approved