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Number of irregular primes less than 3^n.

2

`%I #5 Mar 05 2019 08:37:01
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`%S 0,0,0,3,9,48,131,334,880,2355,6341,17157,47620,132015,366790,1025835,
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`%T 2884928,8143498
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`%N Number of irregular primes less than 3^n.
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`%t ip={ the list of irregular primes to 12 million }; Table[ Length[ Select[ip, # < 3^n &]], {n, 14}]
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`%Y Cf. A055729, A105462, A105467.
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`%K hard,nonn,more
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`%O 1,4
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`%A _Robert G. Wilson v_, Apr 07 2005
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`%E a(15)-a(18) from _Amiram Eldar_, Mar 05 2019
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