Numbers k such that k and k^2 use only the digits 1, 5, 6, 7 and 9.

Terms

a(0) =1a(1) =76a(2) =719a(3) =9569a(4) =9576a(5) =9796a(6) =719666a(7) =756169a(8) =759576a(9) =956619a(10) =957166a(11) =957576a(12) =995576a(13) =7177166a(14) =7179966a(15) =7717966a(16) =75577716a(17) =97956969a(18) =99795669a(19) =99957576a(20) =975559796a(21) =977576169a(22) =995799576a(23) =997995576a(24) =7177576169a(25) =7517976169a(26) =7691917576a(27) =7719565766a(28) =9579956669a(29) =9957999576