a(n) = (1/n) * Sum_{d|n} moebius(n/d) * A002203(d)^2, where A002203 is the companion Pell numbers.
A212443
a(n) = (1/n) * Sum_{d|n} moebius(n/d) * A002203(d)^2, where A002203 is the companion Pell numbers.
Terms
- a(0) =4a(1) =16a(2) =64a(3) =280a(4) =1344a(5) =6496a(6) =32640a(7) =166320a(8) =862400a(9) =4523232a(10) =23970240a(11) =128063040a(12) =689008320a(13) =3728973120a(14) =20285199872a(15) =110841302880a(16) =608029121280
External references
- oeis: A212443