Index at which n first appears in A307720.

Terms

a(0) =1a(1) =3a(2) =5a(3) =27a(4) =47a(5) =99a(6) =53a(7) =137a(8) =177a(9) =1024a(10) =1374a(11) =2474a(12) =1386a(13) =3326a(14) =3662a(15) =5274a(16) =3738a(17) =6290a(18) =3756a(19) =8954a(20) =9374a(21) =12878a(22) =6680a(23) =9682a(24) =9850a(25) =10324a(26) =11010a(27) =14578a(28) =6704a(29) =78506