%I A129756
%S A129756 1,1,1,1,3,3,3,3,5,5,5,5,7,7,7,7,9,9,9,9,11,11,11,11,13,13,13,13,15,15,
%T A129756 15,15,17,17,17,17,19,19,19,19,21,21,21,21,23,23,23,23,25,25,25,25,27,
%U A129756 27,27,27,29,29,29,29,31,31,31,31,33,33,33,33,35,35,35,35,37,37,37,37
%N A129756 Repetitions of odd numbers four times.
%F A129756 a(n) = {Sum_{k=0..n} (k+1)*cos[(n-k)*Pi/2]}+1/4*[2*cos(n*Pi/2)+1+(-1)^n]-1, 
               with n>=0
%F A129756 a(n)=1+2*floor(n/4)=1+2*A002265(n). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), 
               Jun 10 2007
%F A129756 G.f.: (1+x^4)/(-1+x)^2/(1+x)/(x^2+1). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), 
               Nov 18 2007
%F A129756 a(n)=-1+Sum_{k=0..n}{(1/12)*[ -5*(k mod 4)+((k+1) mod 4)+((k+2) mod 4)+7*((k+3) 
               mod 4)]}, with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), Aug 21 2009]
%Y A129756 Sequence in context: A118911 A111756 A130821 this_sequence A156724 A075753 
               A006166
%Y A129756 Adjacent sequences: A129753 A129754 A129755 this_sequence A129757 A129758 
               A129759
%K A129756 easy,nonn
%O A129756 0,5
%A A129756 Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), May 15 2007