a(n) = ((1+4*sqrt(2))*(1+2*sqrt(2))^n + (1-4*sqrt(2))*(1-2*sqrt(2))^n)/2.
A164602
a(n) = ((1+4*sqrt(2))*(1+2*sqrt(2))^n + (1-4*sqrt(2))*(1-2*sqrt(2))^n)/2.
Terms
- a(0) =1a(1) =17a(2) =41a(3) =201a(4) =689a(5) =2785a(6) =10393a(7) =40281a(8) =153313a(9) =588593a(10) =2250377a(11) =8620905a(12) =32994449a(13) =126335233a(14) =483631609a(15) =1851609849a(16) =7088640961a(17) =27138550865a(18) =103897588457a(19) =397765032969
External references
- oeis: A164602