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Expansion of (1+10x)/(1-101x^2).
1

%I #6 Jun 13 2015 00:51:23

%S 1,10,101,1010,10201,102010,1030301,10303010,104060401,1040604010,

%T 10510100501,105101005010,1061520150601,10615201506010,

%U 107213535210701,1072135352107010,10828567056280801,108285670562808010

%N Expansion of (1+10x)/(1-101x^2).

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,101).

%F a(n)=9a(n-1)+10a(n-2)+101^floor((n-2)/2); a(n)=sum{k=0..floor(n/2), binomial(floor(n/2), k)10^(n-2k) }.

%Y Cf. A004663, A026383, A016116, A096881, A096882.

%K easy,nonn

%O 0,2

%A _Paul Barry_, Jul 14 2004