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Numbers n which in decimal have the form imj, where m is the middle digit, with property that j is the reversal of i, and i = m*j.
2

%I #10 Jan 09 2020 14:23:59

%S 111,212,313,414,515,616,717,818,919,11111,22122,33133,44144,55155,

%T 66166,77177,88188,99199,1011101,1111111,1211121,1311131,1411141,

%U 1511151,1611161,1711171,1811181,1911191,2021202,2121212,2221222,2321232,2421242

%N Numbers n which in decimal have the form imj, where m is the middle digit, with property that j is the reversal of i, and i = m*j.

%C The number i should not end in 0, and m should not equal 0.

%C Suggested by _Amarnath Murthy_.

%C Either i and j are identical palindromes and m is 1, or i is in A031877, j is the corresponding term in A008919, and m is either 4 or 9. - _Charlie Neder_, Mar 08 2019

%H Chai Wah Wu, <a href="/A082945/b082945.txt">Table of n, a(n) for n = 1..10000</a>

%e rev(8712) = 2178 and 8712 = 2178*4, so 871242178 is in this sequence. - _Charlie Neder_, Mar 08 2019

%Y Cf. A002113, A008919, A031877. (Possible values of i and j)

%K nonn,base

%O 1,1

%A Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 07 2003

%E Edited by _N. J. A. Sloane_, Oct 25 2009, following discussions on the Sequence Fans Mailing List, circa Apr 17 2009

%E Corrected and extended by _Charlie Neder_, Mar 08 2019