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Column 3 of triangle A113360, also equals column 1 of A113340^7.
4

%I #5 Jun 13 2017 23:05:03

%S 1,21,399,8127,184436,4695719,133730310,4234560596,148077895854,

%T 5680484146379,237574859841676,10771591113205720,526750324271281348,

%U 27655229128194306702,1552379671658643163707,92820542631741826797326

%N Column 3 of triangle A113360, also equals column 1 of A113340^7.

%C A113360 equals the matrix cube of triangle A113340, where column 3 of A113340^3 = column 1 of A113340^7.

%o (PARI) a(n)=local(A,B);A=matrix(1,1);A[1,1]=1;for(m=2,n+4,B=matrix(m,m); for(i=1,m, for(j=1,i,if(i<3 || j==i || j>m-1,B[i,j]=1,if(j==1, B[i,1]=1,B[i,j]=(A^(2*j-1))[i-j+1,1]));));A=B);(A^3)[n+4,4]

%Y Cf. A113340, A113350, A113360 (A113340^3), A113341 (column 0), A113361 (column 1), A113362 (column 2), A113364 (column 4).

%K nonn

%O 0,2

%A _Paul D. Hanna_, Nov 08 2005