%I #6 Mar 18 2021 23:28:52
%S 0,0,0,2,6,16,54,154,480,1418,4302,12836,38670,115802,347868,1042970,
%T 3130350,9389152,28171710,84509410,253541136,760606270,2281857318,
%U 6845520448,20536677354,61609877590,184829980176,554489476858,1663469474178,4990407031696
%N Number of ternary words of length n (beginning 0) with autocorrelation function 2^(n-1)+2.
%F a(2*n) = 3*a(2*n-1) - a(n) - a(n+1) for n>=3; a(2*n-1) = 3*a(2*n-2) + 3*a(n) for n>=3.
%K nonn
%O 1,4
%A TORSTEN.SILLKE(AT)LHSYSTEMS.COM
%E More terms from _Sean A. Irvine_, Mar 18 2021