%I A027831
%S A027831 1,4,14,44,134,400,1184,3488,10252,30096,88296,258960,759368,
%T A027831 2226560,6528256,19140352,56117392,164528960,482376160,
%U A027831 1414257856,4146398048,12156629760,35641443840,104495439360
%N A027831 Expansion of 1/(1-4*x+2*x^2+4*x^3-2*x^4).
%Y A027831 Sequence in context: A094309 A000300 A005323 this_sequence A097894 A065835 
               A097137
%Y A027831 Adjacent sequences: A027828 A027829 A027830 this_sequence A027832 A027833 
               A027834
%K A027831 nonn
%O A027831 0,2
%A A027831 N. J. A. Sloane (njas(AT)research.att.com).