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%I #5 Mar 31 2012 11:28:00
%S 1,625,1715,1925,2125,2875,2975,3575,3773,4165,4225,4235,4625,5125,
%T 5375,5425,5635,5831,5875,5915,6517,6625,7007,7225,7315,7375,7595,
%U 7625,7735,7889,7975,8075,8225,8281,8855,8875,9025,9425,9775,9875,10045,10075
%N Twin natural nonprimes with nonprime number of prime factors.
%C Intersection of A171697 and A167175. [From _R. J. Mathar_, Mar 29 2010]
%e a(1)=1(without prime factors), a(2)=625(=5*5*5*5), a(3)=1715(=5*7*7*7).
%o (PARI) isA171995(n)=n>0&!isprime(n)&((n%6==1&!isprime(n-2))|(n%6==5&!isprime(n+2)))&!isprime(bigomega(n))
%Y Cf. A171697.
%K nonn,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Jan 21 2010
%E Edited and extended by _Charles R Greathouse IV_, Mar 29 2010
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