%I A055560
%S A055560 1,2,6,12,17,44,74,139,1123,1411,2101,4070,11323,11472,12870,16318,
%T A055560 16853,18729,52642,132619,435644,446904,168566853,350096787,521037077,
%U A055560 708609429,1121857192,1641773578,11947307367,21633254881,75356090494
%N A055560 Base numbers of 9-gonal palindromic numbers.
%H A055560 P. De Geest, <a href="http://www.worldofnumbers.com/nona.htm">Palindromic 
               nonagonals</a>
%F A055560 9-gonal numbers are of the form (n(7n-5))/2.
%Y A055560 Cf. A001106, A082723.
%Y A055560 Sequence in context: A130237 A053457 A154030 this_sequence A108727 A138630 
               A026229
%Y A055560 Adjacent sequences: A055557 A055558 A055559 this_sequence A055561 A055562 
               A055563
%K A055560 nonn,base
%O A055560 1,2
%A A055560 J. Lowell (jhbubby(AT)avana.net), Jul 10 2000
%E A055560 Edited and extended by Patrick De Geest (pdg(AT)worldofnumbers.com), 
               Apr 13 2003.