Odd numbers producing 20 even numbers in the Collatz iteration.

Terms

a(0) =43a(1) =131a(2) =133a(3) =397a(4) =405a(5) =433a(6) =435a(7) =441a(8) =475a(9) =1237a(10) =1251a(11) =1285a(12) =1301a(13) =1313a(14) =1325a(15) =1339a(16) =1425a(17) =1427a(18) =1431a(19) =1433a(20) =3861a(21) =3925a(22) =3939a(23) =3941a(24) =3981a(25) =4017a(26) =4019a(27) =4043a(28) =4277a(29) =4293