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%I #7 Mar 30 2012 17:35:24
%S 1,2,5,2,3,8,14,8,3,4,11,20,30,20,11,4,5,14,26,40,55,40,26,14,5,6,17,
%T 32,50,70,91,70,50,32,17,6,7,20,38,60,85,112,140,112,85,60,38,20,7,8,
%U 23,44,70,100,133,168,204,168,133,100,70,44,23,8,9,26,50,80,115,154,196,240,285,240,196,154,115,80,50,26,9
%N Array where the n-th row is the expansion of (1+2*x+...+n*x^(n-1)) * (n+(n-1)*x+...+x^(n-1)).
%e The table starts:
%e 1
%e 2 5 2
%e 3 8 14 8 3
%e 4 11 20 30 20 11 4
%o (PARI) al(n)=Vec(sum(k=1,n,k*x^(k-1))*sum(k=1,n,k*x^(n-k)))
%Y Cf. A005408(row lengths), A000537(row sums), A115262(a rearrangement), A000330(central diagonal).
%K nonn,tabf,easy
%O 1,2
%A _Franklin T. Adams-Watters_, Mar 02 2011
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