Numbers k such that k and k^2 use only the digits 1, 2, 4 and 9.
A137001
Numbers k such that k and k^2 use only the digits 1, 2, 4 and 9.
Terms
- a(0) =1a(1) =2a(2) =11a(3) =12a(4) =21a(5) =212a(6) =221911
External references
- oeis: A137001
A137001
Numbers k such that k and k^2 use only the digits 1, 2, 4 and 9.