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%I #35 Apr 25 2018 19:32:00
%S 1,3,1,10,6,1,33,29,9,1,109,126,57,12,1,360,516,306,94,15,1,1189,2034,
%T 1491,600,140,18,1,3927,7807,6813,3385,1035,195,21,1,12970,29382,
%U 29737,17568,6630,1638,259,24,1,42837,108923,125406,85826,38493,11739,2436,332,27,1
%N Convolution triangle of A006190.
%C As a Riordan array, this is (1/(1-3x-x^2),x/(1-3x-x^2)).
%C T(n,k) is the number of words of length n over {0,1,2,3,4} having k letters 4 and avoiding runs of odd length for the letter 0. - _Milan Janjic_, Jan 14 2017
%H Milan Janjić, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL21/Janjic/janjic93.html">Words and Linear Recurrences</a>, J. Int. Seq. 21 (2018), #18.1.4.
%F Sum_{k=0..n} T(n,k) = A001076(n+1).
%F Sum_{k=0..floor(n/2)} T(n-k,k) = A007482(n).
%F T(n,k) = 3*T(n-1,k) + T(n-1,k-1) + T(n-2,k), T(0,0)=1, T(n,k)=0 if k<0 or k>n. - _Philippe Deléham_, Dec 08 2013
%e Triangle begins:
%e 1;
%e 3, 1;
%e 10, 6, 1;
%e 33, 29, 9, 1;
%e 109, 126, 57, 12, 1;
%e 360, 516, 306, 94, 15, 1;
%e 1189, 2034, 1491, 600, 140, 18, 1;
%e 3927, 7807, 6813, 3385, 1035, 195, 21, 1;
%e 12970, 29382, 29737, 17568, 6630, 1638, 259, 24, 1;
%e 42837, 108923, 125406, 85826, 38493, 11739, 2436, 332, 27, 1;
%e ...
%Y Cf. A006190, A037027, A054456, A112906.
%K easy,nonn,tabl
%O 0,2
%A _Philippe Deléham_, Nov 24 2007
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