Fourth row of A166091. Positions of 7's in A166086.

Terms

a(0) =103a(1) =409a(2) =589a(3) =998a(4) =1297a(5) =1364a(6) =1891a(7) =1952a(8) =2078a(9) =2114a(10) =2119a(11) =2402a(12) =2473a(13) =2485a(14) =2789a(15) =3067a(16) =3182a(17) =3212a(18) =3458a(19) =3611a(20) =3788a(21) =3812a(22) =4022a(23) =4472a(24) =4535a(25) =4579a(26) =5264a(27) =5438a(28) =5763a(29) =5852