Erroneous version of A031976.

Terms

a(0) =2a(1) =3a(2) =5a(3) =6a(4) =7a(5) =8a(6) =2a(7) =3a(8) =5a(9) =6a(10) =7a(11) =8a(12) =2a(13) =2a(14) =22a(15) =23a(16) =2a(17) =25a(18) =26a(19) =27a(20) =28a(21) =2a(22) =3a(23) =3a(24) =32a(25) =33a(26) =3a(27) =35a(28) =36a(29) =37