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%I #18 Aug 14 2023 16:29:40
%S 3,33,663,18445,887313,84946015,3086525013,557027507463,
%T 31110090768183,3404401335645583,609352762511672905
%N a(n) is the smallest positive integer such that a(n) and a(n)+2 are both products of n distinct prime factors.
%e a(2) = 33 = 3 * 11, a(2) + 2 = 35 = 5 * 7.
%e a(3) = 663 = 3 * 13 * 17, a(3) + 2 = 665 = 5 * 7 * 19.
%o (PARI) isok(k, n) = (omega(k)==n) && (omega(k+2)==n) && issquarefree(k) && issquarefree(k+2)
%o a(n) = my(k=1); while (!isok(k, n), k++); k; \\ _Michel Marcus_, Jul 16 2023
%Y Cf. A052215.
%Y Subsequence of A005117.
%K nonn,hard,more
%O 1,1
%A _Tomek Czajka_, Jul 15 2023
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