Numbers with record number of iterations of x -> A306938(x) required to reach 1 (A306944).

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =21a(5) =49a(6) =85a(7) =253a(8) =442a(9) =766a(10) =1327a(11) =2299a(12) =3982a(13) =11839a(14) =20506a(15) =35518a(16) =61519a(17) =184557a(18) =553645a(19) =966928a(20) =1674769a(21) =2900785a(22) =8701141a(23) =25877593a(24) =44821306a(25) =77676682a(26) =134539960a(27) =402368674a(28) =696922987a(29) =1207106023