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%I #7 Dec 16 2017 05:31:38
%S 1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,
%T 1,1,1,1,1,1,1,1,2,1,1,2,2,2,2,1,2,2,1,1,2,2,2,2,1,1,2,1,1,1,1,1,1,1,
%U 1,1,1,1,1,1,1,1,1,2,2,1,1,1,1,2,1,1,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
%N a(n) = A000002(3*n-2), where A000002 is the Kolakoski sequence.
%H Antti Karttunen, <a href="/A156264/b156264.txt">Table of n, a(n) for n = 1..12000</a>
%o (PARI)
%o up_to = 12000;
%o v000002 = [1, 2, 2]; m=3; while(length(v000002) < 3*(1+up_to), v000002 = concat( v000002, vector(v000002[m], i, 2-m%2)); m++); \\ after PARI-code in A000002.
%o A000002(n) = v000002[n];
%o A156264(n) = A000002((3*n)-2); \\ _Antti Karttunen_, Dec 15 2017
%Y Cf. A000002, A074264.
%K nonn
%O 1,7
%A _Benoit Cloitre_, Feb 07 2009