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Table of n, a(n) for n=1..17.
Index entries for linear recurrences with constant coefficients, signature (9,0,1,-9).
G.f.: x*(2+x+2*x^2) / ( (x-1)*(9*x-1)*(1+x+x^2) ). - R. J. Mathar, Apr 26 2015
Sequence in context: A224753 A037558 A037494 * A037742 A037637 A163067
Adjacent sequences: A037571 A037572 A037573 * A037575 A037576 A037577