Row sums of the central coefficients triangle (A163771).

Terms

a(0) =1a(1) =3a(2) =13a(3) =51a(4) =201a(5) =783a(6) =3039a(7) =11763a(8) =45481a(9) =175803a(10) =679779a(11) =2630367a(12) =10187659a(13) =39500373a(14) =153329913a(15) =595883763a(16) =2318471289a(17) =9030982491a(18) =35216266947a(19) =137469149451a(20) =537152523711