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 A239102 Riordan array read by rows, corresponding to g.f. (1+x*y^3)/((1-x-y)*(1+x*y^3)+x*y^4). 1

%I

%S 1,2,1,6,3,1,20,10,4,1,66,35,15,5,1,222,121,56,21,6,1,756,420,204,84,

%T 28,7,1,2598,1464,736,323,120,36,8,1,8994,5122,2643,1215,487,165,45,9,

%U 1,31322,17983,9468,4510,1912,706,220,55,10,1

%N Riordan array read by rows, corresponding to g.f. (1+x*y^3)/((1-x-y)*(1+x*y^3)+x*y^4).

%H Alois P. Heinz, <a href="/A239102/b239102.txt">Rows n = 0..140, flattened</a>

%H D. Baccherini, D. Merlini, R. Sprugnoli, <a href="http://dx.doi.org/10.1016/j.disc.2006.07.023">Binary words excluding a pattern and proper Riordan arrays</a>, Discrete Math. 307 (2007), no. 9-10, 1021--1037. MR2292531 (2008a:05003).

%e Triangle begins:

%e 1

%e 2 1

%e 6 3 1

%e 20 10 4 1

%e 66 35 15 5 1

%e 222 121 56 21 6 1

%e 756 420 204 84 28 7 1

%e 2598 1464 736 323 120 36 8 1

%e ...

%K nonn,tabl

%O 0,2

%A _N. J. A. Sloane_, Mar 25 2014

%E More terms from _Alois P. Heinz_, Sep 03 2014

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Last modified December 15 17:03 EST 2019. Contains 330000 sequences. (Running on oeis4.)