a(0)=1, for n>0: a(n)=2*5^(n-1)-(1/2)Sum a(i)a(n-i),(i=1,..,n-1). 1, 2, 8, 34, 150, 678, 3116, 14494, 68032, 321590, 1528776, 7301142, 35003238
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