Records in A167494.

Terms

a(0) =2a(1) =3a(2) =5a(3) =13a(4) =31a(5) =61a(6) =139a(7) =283a(8) =571a(9) =1153a(10) =2311a(11) =4651a(12) =9343a(13) =19141a(14) =38569a(15) =77419a(16) =154873a(17) =310231a(18) =621631a(19) =1243483a(20) =2486971a(21) =4974721