%I A103973
%S A103973 1,2,4,4,24,16,160,80,1120,448,8064,2688,59136,16896,439296,109824,
%T A103973 3294720,732160,24893440,4978688,189190144,34398208,1444724736,
%U A103973 240787456,11076222976,1704034304,85201715200,12171673600,657270374400
%N A103973 Expansion of (sqrt(1-8x^2)+8x^2+2x-1)/(2x(1-8x^2)).
%F A103973 G.f.: 1/sqrt(1-8x^2)+(1-sqrt(1-8x^2))/(2x); a(n)=sum{k=0..floor(n/2), 
               2^(n-k)*C(k)C(k+1, n-k)}.
%Y A103973 Cf. A025225, A059304.
%Y A103973 Sequence in context: A013140 A155720 A155725 this_sequence A129826 A009296 
               A068554
%Y A103973 Adjacent sequences: A103970 A103971 A103972 this_sequence A103974 A103975 
               A103976
%K A103973 easy,nonn
%O A103973 0,2
%A A103973 Paul Barry (pbarry(AT)wit.ie), Feb 23 2005