%I A028506
%S A028506 1,2,4,10,24,68
%N A028506 Number of non-descending integral vectors b of length n such that number 
               of symmetric 0-1-matrices A of order n with row sums <= b is odd.
%Y A028506 Sequence in context: A003104 A151516 A121186 this_sequence A148088 A029893 
               A148089
%Y A028506 Adjacent sequences: A028503 A028504 A028505 this_sequence A028507 A028508 
               A028509
%K A028506 nonn
%O A028506 1,2
%A A028506 TORSTEN.SILLKE(AT)LHSYSTEMS.COM