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%I #41 May 15 2020 12:24:21
%S 11,88,101,448,673,776,1001,2879,3553,9537,10001,14651,36559,49056,
%T 51073,54116,59600,100001,505025,998999,1000001,4115964,5050250,
%U 5133355,10000001,10050125,19349727,26550976,33726078,35792647,42349456,43605459,50050025,66952741,88027284,88819024,100000001,105124922
%N Numbers k such that (k - digitsum(k))(k + digitsum(k)) contains k as a substring.
%C All numbers of the form 10^n + 1 (for n > 0) are in the sequence.
%H Giovanni Resta, <a href="/A334249/b334249.txt">Table of n, a(n) for n = 1..95</a>
%e 11 is a term as digitsum(11) = 2 and (11 - 2)(11 + 2) = 117, which contains '11' as a substring.
%e 9537 is a term as digitsum(9537) = 24 and (9537 - 24)(9537 + 24) = 90953793, which contains '9537' as a substring.
%Y Cf. A007953, A257784, A125526, A082208, A225780.
%K nonn,base,less
%O 1,1
%A _Scott R. Shannon_, May 05 2020