References to A081178

a(0)=1, for n>=1 a(n)=sum(k=0,n,7^k*N(n,k)) where N(n,k) =1/n*C(n,k)*C(n,k+1) are the Narayana numbers (A001263).
1, 1, 8, 71, 680, 6882, 72528, 788019, 8766248, 99362894, 1143498224

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