%I A138034
%S A138034 1,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,
%T A138034 3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,
%U A138034 1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3,2,1,3
%V A138034 1,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,
               -3,-2,1,3,2,-1,
%W A138034 -3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,
               2,-1,-3,-2,1,3,2,
%X A138034 -1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,
               1,3,2,-1,-3,-2,1,3
%N A138034 Let B_n(x) denote the n-th Boubaker Boubaker (1897-1966) polynomial (see 
               A135935). Then a(n) = B_n(1).
%C A138034 B_n(-1) gives the same sequence up to signs.
%H A138034 Karem Boubaker, <a href="http://www.academicjournals.net/fulltext/tasr/
               2007/540-544.pdf">On modified Boubaker polynomials...</a>, Trends 
               in Appl. Sci. Research, 2 (2007), 540-544.
%H A138034 Karem Boubaker et al., <a href="http://www.epjap.org/index.php?option=article&access=standard&Itemid=129&url=\
               /articles/epjap/pdf/2007/01/ap06126.pdf">Enhancement of pyrolysis 
               spray disposal performance ...</a>, Eur. Phys. J. Appl. Phys., 37 
               (2007), 105-109. [Link requires a subscription]
%H A138034 Hedi Labiadh and Karem Boubaker, <a href="http://www.math.spbu.ru/diffjournal/
               j/EN/numbers/2007.2/article.59.html">A Sturm-Liouville shaped characteristic 
               differential equation ...</a>, Differential Equations and Control 
               Processes, No. 2 (2007).
%F A138034 1, then period 6: repeat 1,3,2,-1,-3,-2 (see A119910).
%F A138034 G.f.: (1+3*t^2)/(1-t+t^2). Boubaker polynomials have generating function 
               (1+3*t^2)/(1-x*t+t^2).
%F A138034 a(n)=3*[C(2*n,n) mod 2]+(1/6)*{-(n mod 6)+2*[(n+1) mod 6]+3*[(n+2) mod 
               6]+[(n+3) mod 6]-2*[(n+4) mod 6]-3*[(n+5) mod 6]}, with n>=0. - Paolo 
               P. Lava (ppl(AT)spl.at), Mar 18 2008
%Y A138034 Equals 1 followed by A119910. Cf. A135935, A135936.
%Y A138034 Sequence in context: A070309 A130784 A119910 this_sequence A087818 A112746 
               A107460
%Y A138034 Adjacent sequences: A138031 A138032 A138033 this_sequence A138035 A138036 
               A138037
%K A138034 sign
%O A138034 0,3
%A A138034 Karem Boubaker (mmbb11112000(AT)yahoo.fr), Mar 01 2008; corrected Mar 
               03 2008