140017878domain: NAppears in sequencesSub-Kaprekar numbers: k such that k = |q - r| and k^2 = q*10^m + r, for some m >= 1, q >= 0, 0 <= r < 10^m, with k not a power of 10.at n=28A118936Sub-Kaprekar numbers (2): n such that n=r-q and n^2=q*10^m+r, for some m>=1, q>=0, 0<=r<10^m, with n not a power of 10.at n=12A118938