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%I #12 Sep 08 2015 17:33:33
%S 1,27,12,19,12,21,10,21,12,19,12,21,10,21,12,19,12,21,10,21,12,19,12,
%T 21,10,21,12,19,12,21,10,21,12,19,12,21,10,21,12,19,12,21,10,21,12,19,
%U 12,21,10,21,12,19,12,21,10,21,12,19,12,21,10,21,12,19,12,21,10,21,12,19
%N a(n) is the number of distinct n-th powers of functions {1, 2, 3} -> {1, 2, 3}.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (-1, 0, 1, 1).
%F For n > 1, a(n) = a(n+6).
%F G.f.: (6*x^5-3*x^4-30*x^3-39*x^2-28*x-1) / ((x-1)*(x+1)*(x^2+x+1)). - _Colin Barker_, Aug 07 2013
%t Join[{1, 27},LinearRecurrence[{-1, 0, 1, 1},{12, 19, 12, 21},68]] (* _Ray Chandler_, Sep 08 2015 *)
%Y Cf. A102687, A102709, A103947, A103949, A103950.
%Y Row n=3 of A247026.
%K easy,nonn
%O 0,2
%A _David Wasserman_, Feb 21 2005