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Table of n, a(n) for n=0..65.
Index entries for linear recurrences with constant coefficients, signature (0,1)
a(n)=-5/2*(-1)^n+15/2 =10*(n mod 2)+5*[(n+1) mod 2] - Paolo P. Lava, Oct 27 2006
G.f.: 5(1+2x)/((1-x)(1+x)). a(n)=5*A000034(n). [From R. J. Mathar, Oct 20 2008]
Sequence in context: A262922 A137404 A110643 * A046795 A229793 A205854
Adjacent sequences: A010718 A010719 A010720 * A010722 A010723 A010724
N. J. A. Sloane.