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%I #11 Aug 12 2023 14:55:31
%S 1546,2066,2234,2554,3334,3566,3814,4586,4894,4946,5422,5594,6098,
%T 6602,6694,6746,7286,7346,7706,7846,7886,8042,8114,8438,8986,9094,
%U 9806,10154,10294,10786,10834,10886,11038,11138,11246,11846,12094,13406,13714,13894,13982,14002,14054
%N Squarefree semiprimes (products of two distinct primes) between sphenic numbers (products of three distinct primes).
%e 1546 = 2*773 (between 1545 = 3*5*103 and 1547 = 7*13*17)
%e 2066 = 2*1033 (between 2065 = 5*7*59 and 2067 = 3*13*53)
%e 2234 = 2*1117 (between 2233 = 7*11*29 and 2235 = 3*5*149)
%t SequencePosition[Table[FactorInteger[n][[;; , 2]], {n, 2, 15000}], {{1, 1, 1}, {1, 1}, {1, 1, 1}}][[;; , 2]] (* _Amiram Eldar_, Apr 23 2023 *)
%Y Cf. A006881, A007304.
%K nonn
%O 1,1
%A _Massimo Kofler_, Apr 23 2023