Interprimes (A024675) which are of the form s*prime, s=21.

Terms

a(0) =42a(1) =105a(2) =231a(3) =399a(4) =483a(5) =861a(6) =987a(7) =1113a(8) =1281a(9) =1491a(10) =1869a(11) =2121a(12) =2247a(13) =2667a(14) =2751a(15) =3129a(16) =3423a(17) =5649a(18) =5691a(19) =5817a(20) =7539a(21) =8169a(22) =8421a(23) =8589a(24) =9807a(25) =10563a(26) =10689a(27) =10983a(28) =11361a(29) =13881