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A185678 Riordan array (((1+x)/(1-x-x^2))^m, x*A000108(x)), m=3.

%I A185678 #18 Oct 30 2022 10:03:31
%S A185678 1,6,1,21,7,1,59,29,8,1,147,97,38,9,1,339,292,145,48,10,1,741,835,496,
%T A185678 204,59,11,1,1557,2347,1606,771,275,71,12,1,3174,6640,5083,2736,1130,
%U A185678 359,84,13,1,6317,19220,16046,9406,4323,1587,457,98,14,1,12330,57469,51152,31932,15886,6480,2157,570,113,15,1
%N A185678 Riordan array (((1+x)/(1-x-x^2))^m, x*A000108(x)), m=3.
%H A185678 Vladimir Kruchinin and D. V. Kruchinin, <a href="http://arxiv.org/abs/1103.2582">Composita and their properties</a>, arXiv:1103.2582 [math.CO], 2011-2013.
%F A185678 R(n,k,m) = k*sum(i=0..n-k, sum(j=m..i+m, binomial(j-1,m-1) * binomial(j,i+m-j)) * binomial(2*(n-i)-k-1,n-i-1)/(n-i)), k>0, m=3, R(n,0,m)=sum(i=m..n+m, binomial(i-1,m-1) * binomial(i,n+m-i)).
%e A185678 1;
%e A185678 6,1;
%e A185678 21,7,1;
%e A185678 59,29,8,1;
%e A185678 147,97,38,9,1;
%e A185678 339,292,145,48,10,1;
%e A185678 741,835,496,204,59,11,1;
%e A185678 1557,2347,1606,771,275,71,12,1;
%Y A185678 Cf. A185675 (m=1), A185676 (m=2).
%K A185678 nonn,tabl
%O A185678 0,2
%A A185678 _Vladimir Kruchinin_, Feb 09 2011