A046836 Internal digits of n^2 include digits of n as substring.

50, 60, 250, 500, 600, 760, 2500, 3760, 3792, 5000, 6000, 6250, 7600, 14651, 25000, 37600, 50000, 60000, 62500, 76000, 93760, 250000, 376000, 495475, 500000, 505025, 600000, 625000, 760000, 906250, 937600, 971582, 1093760, 1713526