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%I #29 Jan 09 2025 10:16:23
%S 9,18,111,212,1128,2067,11123,20270,110440,200971,1101475,2003592,
%T 11005388
%N Number of n-digit numbers N such that the reversal of N divides N.
%C Suggested by A214927.
%C Even terms are roughly double the previous term. - _David Consiglio, Jr._, Mar 22 2013
%H David Consiglio, Jr., <a href="/A222811/a222811.txt">C++ program</a>
%H N. J. A. Sloane, <a href="http://arxiv.org/abs/1307.0453">2178 And All That</a>, Fib. Quart., 52 (2014), 99-120.
%H N. J. A. Sloane, <a href="/A001232/a001232.pdf">2178 And All That</a> [Local copy]
%e Some of the smallest solutions are:
%e [1, 2, 3, 4, 5, 6, 7, 8, 9] (so a(1) = 9),
%e [10, 11, 20, 22, 30, 33, 40, 44, 50, 55, 60, 66, 70, 77, 80, 88, 90, 99] (so a(2) = 18),
%e [100, 101, 110, 111, 121, 131, 141, 151, 161, 171, 181, 191, 200, 202, 212, 220, 222, 232, 242, 252, 262, 272, 282, 292, 300, 303, 313, 323, 330, 333, 343, 353, ...]
%Y Cf. A214927, A222809, A222810, A222812.
%K nonn,base,more,changed
%O 1,1
%A _N. J. A. Sloane_, Mar 10 2013
%E a(8) - a(11) from _David Consiglio, Jr._, Mar 22 2013
%E a(12)-a(13) from _Giovanni Resta_, Apr 01 2013