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%I #26 May 31 2022 12:53:37
%S 1,5,7,13,17,23,25,29,31,37,41,43,49,51,55,59,61,67,71,73,79,85,91,95,
%T 97,101,103,109,113,115,121,125,131,133,137,141,143,149,155,157,161,
%U 167,173,175,179,185,187,191,193,199,201,205,209,211,217,221,223,227,229
%N Positions of 1's when Kolakoski sequence is grouped into four independent numbers as 1, 2, 11, 22.
%e A000002 can be grouped as 1, 22, 11, 2, 1, 22, 1, 22, 11, 2, ... The positions of occurrence of 1's (1, 5, 7, ...) are given in this sequence.
%t s = {1, 2, 2}; Do[s = Append[s, Mod[n-1, 2] + 1], {n, 3, 230}, {s[[n]]}]; Position[Split[s], {1}] // Flatten (* _Amiram Eldar_, Jul 24 2020 *)
%Y Cf. A000002.
%K nonn
%O 1,2
%A _Rakesh Khanna A_, May 22 2020