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A334249
Numbers k such that (k - digitsum(k))(k + digitsum(k)) contains k as a substring.
1
11, 88, 101, 448, 673, 776, 1001, 2879, 3553, 9537, 10001, 14651, 36559, 49056, 51073, 54116, 59600, 100001, 505025, 998999, 1000001, 4115964, 5050250, 5133355, 10000001, 10050125, 19349727, 26550976, 33726078, 35792647, 42349456, 43605459, 50050025, 66952741, 88027284, 88819024, 100000001, 105124922
OFFSET
1,1
COMMENTS
All numbers of the form 10^n + 1 (for n > 0) are in the sequence.
LINKS
EXAMPLE
11 is a term as digitsum(11) = 2 and (11 - 2)(11 + 2) = 117, which contains '11' as a substring.
9537 is a term as digitsum(9537) = 24 and (9537 - 24)(9537 + 24) = 90953793, which contains '9537' as a substring.
CROSSREFS
KEYWORD
nonn,base,less
AUTHOR
Scott R. Shannon, May 05 2020
STATUS
approved