%I A020541
%S A020541 5,209,3905,64769,1045505,16764929,268386305,4294770689,
%T A020541 68718690305,1099508482049,17592173461505,281474926379009,
%U A020541 4503599426043905,72057593232621569,1152921501385621505
%N A020541 4th Chebyshev polynomial (second kind) evaluated at powers of 2.
%H A020541 <a href="Sindx_Ch.html#Cheby">Index entries for sequences related to 
               Chebyshev polynomials.</a>
%F A020541 16^(n+1) - 3*4^(n+1) + 1.
%p A020541 with(orthopoly):seq(U(4,2^i),i=0..24);
%t A020541 Table[ChebyshevU[4,2^n],{n,1,40}] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), 
               Nov 03 2009]
%Y A020541 Sequence in context: A162087 A068531 A144139 this_sequence A027682 A006413 
               A055316
%Y A020541 Adjacent sequences: A020538 A020539 A020540 this_sequence A020542 A020543 
               A020544
%K A020541 nonn
%O A020541 0,1
%A A020541 Simon Plouffe (simon.plouffe(AT)gmail.com)