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%I #23 Sep 03 2018 22:54:49
%S 0,1,45,55,99
%N 2-White numbers (take power 2, sum 2-digit groups to get same number).
%C Also, apart from initial 0, the full list of 2-Kaprekar numbers.
%D Italo Ghersi, Matematica dilettevole e curiosa, p. 190, Hoepli, Milano, 1967. [_Vincenzo Librandi_, Apr 22 2010]
%H D. E. Iannucci, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL3/iann2a.html">The Kaprekar numbers</a>, J. Integer Sequences, Vol. 3, 2000, #1.2.
%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%e 45 is a 2-White number since 45^2 = 2025 and 20 + 25 = 45.
%K full,nonn,fini,base
%O 1,3
%A _Erich Friedman_
%E Offset set to 1 by _Paolo P. Lava_, Jul 12 2016