Numbers k such that k^2 contains only digits {2,4,9}.

Terms

a(0) =2a(1) =3a(2) =7a(3) =173a(4) =212a(5) =307a(6) =1557a(7) =3038a(8) =4788a(9) =6557a(10) =9607a(11) =70173a(12) =222327a(13) =649788a(14) =7015857a(15) =17173882a(16) =22349368a(17) =30402212a(18) =1514009327a(19) =5470304327a(20) =67081614057a(21) =171739460943a(22) =205534649693a(23) =473521111382a(24) =666553067838