%I A101399
%S A101399 1,2,5,10,22,47,101,217,466,1001,2150,4618,9919,21305,45761,98290,
%T A101399 211117,453458,973982,2092015,4493437,9651449,20730338,44526673,
%U A101399 95638798,205422482,441226751,947710513,2035586497,4372234274
%N A101399 a(0) = 1, a(1) = 2, a(2) = 5; for n >= 3, a(n) = a(n - 1) + 2*a(n - 2) 
               + a(n - 3)
%C A101399 Lengths of successive words (starting with a) under the substitution: 
               {a -> ab, b -> aac, c -> a}.
%t A101399 a[0] = 1; a[1] = 2; a[2] = 5; a[n_] := a[n] = a[n - 1] + 2a[n - 2] + 
               a[n - 3]; Table[ a[n], {n, 0, 30}] (from Robert G. Wilson v Jan 15 
               2005)
%Y A101399 Pairwise sums of A078007. Bisection of A003410 and A058278.
%Y A101399 Sequence in context: A018004 A124329 A144520 this_sequence A018109 A123491 
               A166300
%Y A101399 Adjacent sequences: A101396 A101397 A101398 this_sequence A101400 A101401 
               A101402
%K A101399 nonn,easy
%O A101399 0,2
%A A101399 J. F. J. Laros (jlaros(AT)liacs.nl), Jan 15 2005
%E A101399 More terms from Robert G. Wilson v (rgwv(AT)rgwv.com) and Lior Manor 
               (lior.manor(AT)gmail.com) Jan 15 2005