Position of n-th 7 in A031100.

Terms

a(0) =4a(1) =22a(2) =40a(3) =58a(4) =59a(5) =61a(6) =63a(7) =65a(8) =67a(9) =76a(10) =103a(11) =130a(12) =157a(13) =174a(14) =177a(15) =180a(16) =183a(17) =184a(18) =211a(19) =238a(20) =265a(21) =292a(22) =294a(23) =297a(24) =300a(25) =303a(26) =306a(27) =319a(28) =346a(29) =373