a(n) = Sum{(k+1)*T(n,m-k)}, 0<=k<=m, where m=0 for n=1; m=n+1 for n >= 2; T given by A026148. 1, 3, 18, 54, 162, 486, 1458, 4374, 13122, 39366, 118098, 354294, 1062882
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