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%I #7 Oct 27 2019 00:34:12
%S 128,2187,78125,496875,823543,1908795,3680733,6280989,11447205,
%T 11639595,14480427,15839397,15988245,17998875,19165069,19487171,
%U 22073667,22444653,27340845,30830163,35277795,38975433,44183867
%N Concatenation of the 7 prime factors of composite a(n) is a palindrome.
%e 17998875 = 3 * 3 * 3 * 5 * 5 * 5 * 5333 -> 3335555333 is palindromic.
%Y Cf. A046447.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Jul 15 1998
%E Edited by _Charles R Greathouse IV_, Apr 28 2010