a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026769.
A027241
a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026769.
Terms
- a(0) =1a(1) =7a(2) =38a(3) =201a(4) =991a(5) =5119a(6) =25108a(7) =131207a(8) =652171a(9) =3467959a(10) =17536482a(11) =94772169a(12) =487259131a(13) =2668269045a(14) =13920305080a(15) =77008669339a(16) =406737748473
External references
- oeis: A027241