%I A056470
%S A056470 1,1,2,2,5,5,15,15,52,52,202,202,855,855,3845,3845,18002,18002,86472,
%T A056470 86472,422005,422005,2079475,2079475,10306752,10306752,51263942,
%U A056470 51263942,255514355,255514355,1275163905
%N A056470 Number of palindromic structures using a maximum of five different symbols.
%C A056470 Permuting the symbols will not change the structure.
%D A056470 M. R. Nester (1999). Mathematical investigations of some plant interaction 
               designs. PhD Thesis. University of Queensland, Brisbane, Australia.
%F A056470 Sum stirling2( [(n+1)/2], k) for k from 1 to 5.
%Y A056470 Cf. A056451.
%Y A056470 Sequence in context: A098887 A097438 A055879 this_sequence A056471 A164904 
               A083849
%Y A056470 Adjacent sequences: A056467 A056468 A056469 this_sequence A056471 A056472 
               A056473
%K A056470 nonn
%O A056470 1,3
%A A056470 Marks R. Nester (nesterm(AT)dpi.qld.gov.au)