Partial sums of A001935; at one time this was conjectured to agree with A007478.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =5a(7) =8a(8) =12a(9) =18a(10) =27a(11) =39a(12) =55a(13) =77a(14) =106a(15) =144a(16) =194a(17) =258a(18) =340a(19) =445a(20) =577a(21) =743a(22) =951a(23) =1209a(24) =1529a(25) =1924a(26) =2408a(27) =3000a(28) =3722a(29) =4598