a(n) = n * Fibonacci(2n).

Terms

a(0) =0a(1) =1a(2) =6a(3) =24a(4) =84a(5) =275a(6) =864a(7) =2639a(8) =7896a(9) =23256a(10) =67650a(11) =194821a(12) =556416a(13) =1578109a(14) =4449354a(15) =12480600a(16) =34852944a(17) =96949079a(18) =268746336a(19) =742675211a(20) =2046683100a(21) =5626200216a(22) =15430992126a(23) =42235173769a(24) =115380647424a(25) =314656725625a(26) =856733282574