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 A320629 Products of odd primes of nonprime index. 5
 1, 7, 13, 19, 23, 29, 37, 43, 47, 49, 53, 61, 71, 73, 79, 89, 91, 97, 101, 103, 107, 113, 131, 133, 137, 139, 149, 151, 161, 163, 167, 169, 173, 181, 193, 197, 199, 203, 223, 227, 229, 233, 239, 247, 251, 257, 259, 263, 269, 271, 281, 293, 299, 301, 307, 311 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The index of a prime number n is the number m such that n is the m-th prime. LINKS EXAMPLE The sequence of terms begins:     1 = 1     7 = prime(4)    13 = prime(6)    19 = prime(8)    23 = prime(9)    29 = prime(10)    37 = prime(12)    43 = prime(14)    47 = prime(15)    49 = prime(4)^2    53 = prime(16)    61 = prime(18)    71 = prime(20)    73 = prime(21)    79 = prime(22)    89 = prime(24)    91 = prime(4)*prime(6)    97 = prime(25)   101 = prime(26)   103 = prime(27)   107 = prime(28)   113 = prime(30)   131 = prime(32)   133 = prime(4)*prime(8)   137 = prime(33)   139 = prime(34)   149 = prime(35)   151 = prime(36)   161 = prime(4)*prime(9) MATHEMATICA Select[Range[1, 100, 2], And@@Not/@PrimeQ/@PrimePi/@First/@FactorInteger[#]&] CROSSREFS Cf. A000040, A006450, A007821, A018252, A056239, A076610, A112798, A302242, A320533, A320628, A320630, A320631, A320633. Sequence in context: A092409 A124095 A109369 * A309649 A088982 A176406 Adjacent sequences:  A320626 A320627 A320628 * A320630 A320631 A320632 KEYWORD nonn AUTHOR Gus Wiseman, Oct 18 2018 STATUS approved

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Last modified October 16 03:15 EDT 2019. Contains 328038 sequences. (Running on oeis4.)