a(n) = Sum_{k=0..floor(n/2)} binomial(2n-2k,2k)3^k*2^(n-k).
A108486
a(n) = Sum_{k=0..floor(n/2)} binomial(2n-2k,2k)3^k*2^(n-k).
Terms
- a(0) =1a(1) =2a(2) =10a(3) =80a(4) =412a(5) =2456a(6) =14680a(7) =85376a(8) =503056a(9) =2959136a(10) =17381536a(11) =102199040a(12) =600757696a(13) =3531251072a(14) =20758107520a(15) =122021457920a(16) =717273440512
External references
- oeis: A108486