A047121 Sum{T(i,n-i): i=0,1,...,n}, array T as in A047120.
1, 2, 3, 5, 9, 18, 36, 69, 134, 263, 526, 1052, 2085, 4143, 8250, 16500, 33000, 65851, 131484, 262668, 525336, 1050672, 2100045, 4198157, 8393603, 16787206, 33574412, 67136750, 134255332, 268484858, 536969716, 1073939432, 2147761687
Offset: 0