Trimorphic number

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In mathematics a trimorphic number is a number whose cube (expressed in a given base) ends in the number itself. For example, 43 = 64, 243 = 13824, and 2493 = 15438249.

The first few trimorphic numbers in base 10 are:

1, 4, 5, 6, 9, 24, 25, 49, 51, 75, 76, 99, 125, 249, 251, 375, 376, 499, 501, 624, 625, 749, 751, 875, 999, 1249, 3751, 4375, 4999, 5001, 5625, 6249, 8751, 9375, 9376, 9999, ... (sequence A033819 in OEIS)

Every automorphic number is also a trimorphic number, but there are trimorphic numbers which are not automorphic (such as 4, 9 and 24).

References[edit]

Weisstein, Eric W., "Trimorphic Number", MathWorld.