Numbers such that the three numbers before and the three numbers after are squarefree semiprimes.

Terms

a(0) =216a(1) =143100a(2) =194760a(3) =206136a(4) =273420a(5) =684900a(6) =807660a(7) =1373940a(8) =1391760a(9) =1516536a(10) =1591596a(11) =1611000a(12) =1774800a(13) =1882980a(14) =1891764a(15) =2046456a(16) =2051496a(17) =2163420a(18) =2163960a(19) =2338056a(20) =2359980a(21) =2522520a(22) =2913840a(23) =3108204a(24) =4221756a(25) =4297320a(26) =4334940a(27) =4866120a(28) =4988880a(29) =5108796