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%I #11 Jan 06 2021 16:18:31
%S 10,22,34,46,55,62,82,85,94,115,118,134,146,155,166,187,194,205,206,
%T 218,235,253,254,274,295,298,314,334,335,341,358,365,382,391,394,415,
%U 422,451,454,466,482,485,514,515,517,527,538,545,554,566,614,626,635,649
%N Numbers of the form prime(x) * prime(y) where x and y are distinct and both odd.
%C The squarefree semiprimes in A332822. - _Peter Munn_, Dec 25 2020
%F Numbers m such that A001221(m) = A001222(m) = A195017(m) = 2. - _Peter Munn_, Dec 31 2020
%e The sequence of terms together with their prime indices begins:
%e 10: {1,3} 187: {5,7} 358: {1,41} 527: {7,11}
%e 22: {1,5} 194: {1,25} 365: {3,21} 538: {1,57}
%e 34: {1,7} 205: {3,13} 382: {1,43} 545: {3,29}
%e 46: {1,9} 206: {1,27} 391: {7,9} 554: {1,59}
%e 55: {3,5} 218: {1,29} 394: {1,45} 566: {1,61}
%e 62: {1,11} 235: {3,15} 415: {3,23} 614: {1,63}
%e 82: {1,13} 253: {5,9} 422: {1,47} 626: {1,65}
%e 85: {3,7} 254: {1,31} 451: {5,13} 635: {3,31}
%e 94: {1,15} 274: {1,33} 454: {1,49} 649: {5,17}
%e 115: {3,9} 295: {3,17} 466: {1,51} 662: {1,67}
%e 118: {1,17} 298: {1,35} 482: {1,53} 685: {3,33}
%e 134: {1,19} 314: {1,37} 485: {3,25} 694: {1,69}
%e 146: {1,21} 334: {1,39} 514: {1,55} 697: {7,13}
%e 155: {3,11} 335: {3,19} 515: {3,27} 706: {1,71}
%e 166: {1,23} 341: {5,11} 517: {5,15} 713: {9,11}
%t Select[Range[100],SquareFreeQ[#]&&PrimeOmega[#]==2&&OddQ[Times@@PrimePi/@First/@FactorInteger[#]]&]
%Y A338910 is the not necessarily squarefree version.
%Y A339004 is the even instead of odd version.
%Y A001358 lists semiprimes, with odd and even terms A046315 and A100484.
%Y A005117 lists squarefree numbers.
%Y A006881 lists squarefree semiprimes, with odd and even terms A046388 and A100484.
%Y A289182/A115392 list the positions of odd/even terms of A001358.
%Y A300912 lists products of two primes of relatively prime index.
%Y A320656 counts factorizations into squarefree semiprimes.
%Y A338898, A338912, and A338913 give the prime indices of semiprimes, with product A087794, sum A176504, and difference A176506.
%Y A338899, A270650, and A270652 give the prime indices of squarefree semiprimes, with difference A338900.
%Y A338904 groups semiprimes by weight.
%Y A338906/A338907 list semiprimes of even/odd weight.
%Y A339002 lists products of two distinct primes of non-relatively prime index.
%Y A339005 lists products of two distinct primes of divisible index.
%Y Cf. A001221, A001222, A056239, A112798, A166237, A195017, A318990, A320911, A338901, A338903, A338911.
%Y Subsequence of A332822.
%K nonn
%O 1,1
%A _Gus Wiseman_, Nov 21 2020
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