a(n) = (1/n) * Sum_{i=0..n-1} C(n,i)*C(n,i+1)*2^i*3^(n-i), a(0)=1.
A103210
a(n) = (1/n) * Sum_{i=0..n-1} C(n,i)*C(n,i+1)*2^i*3^(n-i), a(0)=1.
Terms
- a(0) =1a(1) =3a(2) =15a(3) =93a(4) =645a(5) =4791a(6) =37275a(7) =299865a(8) =2474025a(9) =20819307a(10) =178003815a(11) =1541918901a(12) =13503125805a(13) =119352115551
External references
- oeis: A103210