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%I A124317
%S A124317 22,34,51,57,82,85,87,123,133,134,146,158,201,205,209,214,221,227,237,
%T A124317 295,305,309,321,327,341,361,365,371,394,395,447,478,481,497,501,529,
%U A124317 533,543,545,551,554,559,583,597,614,623,635,689,699,734,763,766,781
%N A124317 Semiprimes indexed by 3-almost primes.
%C A124317 Note that a(10)-a(9) = a(30)-a(29) = 1, achieving the minimum possible, 
               due to a combination of the appropriate semiprime gap (A065516) and 
               3-almost prime gap (A114403).
%F A124317 a(n) = semiprime(3almostprime(n)) = A001358(A14612(n)).
%e A124317 a(1) = semiprime(3almostprime(1)) = semiprime(8 = 2^3) = 22 = 2 * 11.
%e A124317 a(2) = semiprime(3almostprime(2)) = semiprime(12 = 2^2 * 3) = 34 = 2 
               * 17.
%e A124317 a(3) = semiprime(3almostprime(3)) = semiprime(18 = 2 * 3^2) = 51 = 3 
               * 17.
%Y A124317 Cf. A124318 3-almost primes indexed by semiprimes. A124319 semiprime(3almostprime(n)) 
               - 3almostprime(semiprime(n)). A124308 Primes indexed by 5-almost 
               primes. A124309 5-almost primes indexed by primes. A124310 prime(5almostprime(n)) 
               - 5almostprime(prime(n)). 4-almost primes indexed by primes = A124283. 
               prime(4almostprime(n)) - 4almostprime(prime(n)) = A124284. Primes 
               indexed by 3-almost primes = A124268. 3-almost primes indexed by 
               primes = A124269. prime(3almostprime(n)) - 3almostprime(prime(n)) 
               = A124270. See also A106349 Primes indexed by semiprimes. See also 
               A106350 Semiprimes indexed by primes. See also A122824 Prime(semiprime(n)) 
               - semiprime(prime(n)). Commutator [A000040, A001358] at n.
%Y A124317 Cf. A000040, A001358, A014612, A065516, A114403, A122824, A124269, A124270, 
               A124282-A124284, A124309, A124310, A124318, A124319.
%Y A124317 Sequence in context: A071265 A103320 A125526 this_sequence A159518 A100039 
               A061561
%Y A124317 Adjacent sequences: A124314 A124315 A124316 this_sequence A124318 A124319 
               A124320
%K A124317 easy,nonn,less
%O A124317 1,1
%A A124317 Jonathan Vos Post (jvospost3(AT)gmail.com), Oct 26 2006

    
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Last modified November 23 17:09 EST 2009. Contains 167438 sequences.


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