Triangular numbers which are 4-almost primes.

Terms

a(0) =36a(1) =136a(2) =210a(3) =276a(4) =351a(5) =666a(6) =820a(7) =1035a(8) =1225a(9) =1275a(10) =1326a(11) =1431a(12) =1770a(13) =1830a(14) =1953a(15) =2145a(16) =2346a(17) =2415a(18) =2775a(19) =2926a(20) =3003a(21) =3486a(22) =3916a(23) =4005a(24) =4186a(25) =4278a(26) =5050a(27) =5356a(28) =5565a(29) =6105