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%I #7 Mar 25 2014 10:48:15
%S 1,2,1,6,3,1,18,9,4,1,58,29,13,5,1,192,96,44,18,6,1,650,325,151,64,24,
%T 7,1,2232,1116,524,228,90,31,8,1,7746,3873,1833,813,333,123,39,9,1,
%U 27096,13548,6452,2904,1222,473,164,48,10,1
%N Riordan array (1/u,(1-u)/2), u=sqrt(1-4x+4*x^3).
%C T(n,0) = A157004(n).
%D Baccherini, D.; Merlini, D.; Sprugnoli, R. Binary words excluding a pattern and proper Riordan arrays. Discrete Math. 307 (2007), no. 9-10, 1021--1037. MR2292531 (2008a:05003). See Example 5.6. - _N. J. A. Sloane_, Mar 25 2014
%F T(n,0)=2*T(n,1) for n>0, T(0,0)=1, T(n,k)=T(n-1,k-1)-T((n-3,k-1)+T(n,k+1).
%e Triangle begins :
%e 1
%e 2 1
%e 6 3 1
%e 18 9 4 1
%e 58 29 13 5 1
%e 192 96 44 18 6 1
%e 650 325 151 64 24 7 1
%e ...
%Y Cf. A025262, A157004
%K nonn,tabl
%O 0,2
%A _Philippe Deléham_, Nov 19 2009
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