Omit the 1s from first differences of A084663.

Terms

a(0) =2a(1) =7a(2) =13a(3) =5a(4) =29a(5) =3a(6) =59a(7) =3a(8) =7a(9) =5a(10) =3a(11) =131a(12) =3a(13) =263a(14) =3a(15) =17a(16) =3a(17) =5a(18) =3a(19) =19a(20) =569a(21) =3a(22) =17a(23) =3a(24) =13a(25) =7a(26) =5a(27) =3a(28) =1181a(29) =3