Number of integers in n-th generation of tree T(3/4) defined in Comments.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =2a(7) =3a(8) =3a(9) =5a(10) =5a(11) =7a(12) =8a(13) =11a(14) =12a(15) =16a(16) =18a(17) =24a(18) =28a(19) =35a(20) =41a(21) =53a(22) =63a(23) =79a(24) =95a(25) =119a(26) =145a(27) =181a(28) =221a(29) =275