G.f.: Sum_{n>=0} Product_{k=1..n} ((1+2*x)^k - 1)/((1+2*x)^k + 1).
A208816
G.f.: Sum_{n>=0} Product_{k=1..n} ((1+2*x)^k - 1)/((1+2*x)^k + 1).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =3a(4) =9a(5) =39a(6) =193a(7) =1135a(8) =7585a(9) =57055a(10) =476161a(11) =4366399a(12) =43627393a(13) =471693439a(14) =5486186497a(15) =68296367871a(16) =906012795393
External references
- oeis: A208816