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%I #11 Feb 20 2017 23:19:20
%S 0,2,8,12,16,18,20,24,28,30,32,36,40,42,44,48,50,52,54,56,60,64,66,68,
%T 70,72,76,78,80,84,88,90,92,96,98,100,102,104,108,110,112,114,116,120,
%U 124,126,128,130,132,136,138,140,144,148,150,152,154,156,160,162,164
%N Even numbers that are not semiprimes, or, twice the nonprimes.
%F a(n)= 2*A141468(n).
%F A005843 \ A100484.
%F a(n) = A139270(n-1). [_R. J. Mathar_, May 03 2010]
%t 2 Prepend[Select[Range@ 82, ! PrimeQ@ # &], 0] (* _Michael De Vlieger_, Feb 20 2017 *)
%o (PARI) isok(n) = !(n%2) && !isprime(n/2); \\ _Michel Marcus_, Feb 20 2017
%Y Cf. A001358, A005843, A100484, A141468.
%K nonn,easy
%O 1,2
%A _Juri-Stepan Gerasimov_, Apr 08 2010, Apr 11 2010
%E Entries checked by _R. J. Mathar_, Apr 16 2010