Number of admissible sequences of order j; related to 3x+1 problem and Wagon's constant.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =12a(6) =30a(7) =85a(8) =173a(9) =476a(10) =961a(11) =2652a(12) =8045a(13) =17637a(14) =51033a(15) =108950a(16) =312455a(17) =663535a(18) =1900470a(19) =5936673a(20) =13472296a(21) =39993895a(22) =87986917a(23) =257978502a(24) =820236724a(25) =1899474678a(26) =5723030586a(27) =12809477536a(28) =38036848410a(29) =84141805077