a(n) is the least positive number k such that k^2 is the concatenation of m and m + n for some positive number m, or -1 if there is no such k.
A369689
a(n) is the least positive number k such that k^2 is the concatenation of m and m + n for some positive number m, or -1 if there is no such k.
Terms
- a(0) =36363636364a(1) =428a(2) =8874a(3) =5a(4) =310a(5) =4a(6) =39a(7) =-1a(8) =7747a(9) =465
External references
- oeis: A369689