G.f.: exp( Sum_{n>=1} 2*Pell(n)^2 * x^n/n ), where Pell(n) = A000129(n).
A208034
G.f.: exp( Sum_{n>=1} 2*Pell(n)^2 * x^n/n ), where Pell(n) = A000129(n).
Terms
- a(0) =1a(1) =2a(2) =6a(3) =26a(4) =122a(5) =602a(6) =3062a(7) =15906a(8) =83906a(9) =447842a(10) =2412566a(11) =13094490a(12) =71513210a(13) =392592410a(14) =2164815590a(15) =11982792386a(16) =66548673282a(17) =370672213826
External references
- oeis: A208034