Semiprime centered triangular numbers.

Terms

a(0) =4a(1) =10a(2) =46a(3) =85a(4) =166a(5) =235a(6) =274a(7) =361a(8) =514a(9) =694a(10) =901a(11) =1135a(12) =1219a(13) =1306a(14) =1585a(15) =1891a(16) =2461a(17) =2839a(18) =3106a(19) =3385a(20) =3826a(21) =3979a(22) =4135a(23) =5311a(24) =5674a(25) =6049a(26) =6241a(27) =6835a(28) =7246a(29) =8551