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A105456
Number of irregular primes less than 2^n.
2
0, 0, 0, 0, 0, 2, 5, 9, 28, 64, 124, 225, 408, 763, 1378, 2566, 4803, 9005, 16948, 32300, 61408, 116688, 222093, 424411, 812236, 1556827, 2991345, 5756015, 11089585, 21403049
OFFSET
1,6
MATHEMATICA
ip={ the list of irregular primes to 12 million }; Table[ Length[ Select[ip, # < 2^n &]], {n, 23}]
CROSSREFS
KEYWORD
hard,nonn,more
AUTHOR
Robert G. Wilson v, Apr 07 2005
EXTENSIONS
a(23) corrected and a(24)-a(40) added by Amiram Eldar, Mar 05 2019
STATUS
approved