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%I #5 Nov 20 2015 15:58:53
%S 131,223,359,409,593,613,659,953,997,1049,1069,1223,1283,1543,1601,
%T 1693,1733,1747,1811,1987,2003,2069,2503,2593,2693,2713,2789,2801,
%U 2903,3079,3181,3221,3301,3323,3541,3571,3727,4003,4127,4283
%N Primes indexed by 5-almost primes.
%F a(n) = prime(5almostprime(n)) = A000040(A014614(n)). {p such that p is prime and omega(primepi(p)) = 5} = {p such that p is in A000040 and A001222(A000720(p)) = 5}.
%e a(1) = prime(5almostprime(1)) = prime(32 = 2^5) = 131.
%e a(2) = prime(5almostprime(2)) = prime(48 = 2^4 * 3) = 223.
%e a(3) = prime(5almostprime(3)) = prime(72 = 2^3 * 3^2) = 359.
%e a(4) = prime(5almostprime(4)) = prime(80 = 2^4 * 5) = 409.
%t Prime[#]&/@Select[Range[600],PrimeOmega[#]==5&] (* _Harvey P. Dale_, Nov 20 2015 *)
%Y Cf. 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 Cf. A000040, A014614, A114405, A114415, A122824, A124269, A124270, A124282-A124284, A124309, A124310.
%K easy,nonn,less
%O 1,1
%A _Jonathan Vos Post_, Oct 25 2006
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