Numbers having four 7's in base 8.

Terms

a(0) =4095a(1) =8191a(2) =12287a(3) =16383a(4) =20479a(5) =24575a(6) =28671a(7) =29183a(8) =29695a(9) =30207a(10) =30719a(11) =31231a(12) =31743a(13) =32255a(14) =32319a(15) =32383a(16) =32447a(17) =32511a(18) =32575a(19) =32639a(20) =32703a(21) =32711a(22) =32719a(23) =32727a(24) =32735a(25) =32743a(26) =32751a(27) =32759a(28) =32760a(29) =32761