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%I #5 Oct 18 2018 08:50:23
%S 2,4,8,13,16,26,29,32,43,47,52,58,64,73,79,86,94,101,104,113,116,128,
%T 137,139,146,149,158,163,167,169,172,181,188,199,202,208,226,232,233,
%U 256,257,269,271,274,278,292,293,298,313,316,317,326,334,338,344,347
%N Products of primes of nonprime squarefree index.
%C The index of a prime number n is the number m such that n is the m-th prime.
%e The sequence of terms begins:
%e 2 = prime(1)
%e 4 = prime(1)^2
%e 8 = prime(1)^3
%e 13 = prime(6)
%e 16 = prime(1)^4
%e 26 = prime(1)*prime(6)
%e 29 = prime(10)
%e 32 = prime(1)^5
%e 43 = prime(14)
%e 47 = prime(15)
%e 52 = prime(1)^2*prime(6)
%e 58 = prime(1)*prime(10)
%e 64 = prime(1)^6
%e 73 = prime(21)
%e 79 = prime(22)
%e 86 = prime(1)*prime(14)
%e 94 = prime(1)*prime(15)
%e 101 = prime(26)
%e 104 = prime(1)^3*prime(6)
%e 113 = prime(30)
%e 116 = prime(1)^2*prime(10)
%e 128 = prime(1)^7
%t Select[Range[100],With[{f=PrimePi/@First/@FactorInteger[#]},And[And@@SquareFreeQ/@f,And@@Not/@PrimeQ/@f]]&]
%Y Cf. A000040, A006450, A007821, A018252, A056239, A076610, A112798, A302242, A302478, A320628, A320629, A320631, A320633.
%K nonn
%O 1,1
%A _Gus Wiseman_, Oct 18 2018
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