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%I #5 Jun 13 2017 22:51:32
%S 1,6,51,561,7726,129406,2572892,59525136,1576414408,47144606666,
%T 1574176301192,58126182666796,2354183194432226,103850488571214174,
%U 4959424774062415780,255032863135423053615,14056171975717324065788
%N Column 2 of triangle A113350, also equals column 0 of A113340^6.
%o (PARI) a(n)=local(A,B);A=matrix(1,1);A[1,1]=1;for(m=2,n+1,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^6)[n+1,1]
%Y Cf. A113340, A113350, A113346 (column 0), A113351 (column 1), A113353 (column 3), A113354 (column 4).
%K nonn
%O 0,2
%A _Paul D. Hanna_, Nov 08 2005