<Dd> (n 1) + (n 4) + (n 7) + ⋯ = 1 3 (2 n + 2 cos ⁡ (n − 2) π 3) (\ displaystyle (\ binom (n) (1)) + (\ binom (n) (4)) + (\ binom (n) (7)) + \ cdots = (\ frac (1) (3)) \ left (2 ^ (n) + 2 \ cos (\ frac ((n - 2) \ pi) (3)) \ right)) </Dd> <Dl> <Dd> (n 2) + (n 5) + (n 8) + ⋯ = 1 3 (2 n + 2 cos ⁡ (n − 4) π 3) (\ displaystyle (\ binom (n) (2)) + (\ binom (n) (5)) + (\ binom (n) (8)) + \ cdots = (\ frac (1) (3)) \ left (2 ^ (n) + 2 \ cos (\ frac ((n - 4) \ pi) (3)) \ right)) </Dd> </Dl> <Dd> (n 2) + (n 5) + (n 8) + ⋯ = 1 3 (2 n + 2 cos ⁡ (n − 4) π 3) (\ displaystyle (\ binom (n) (2)) + (\ binom (n) (5)) + (\ binom (n) (8)) + \ cdots = (\ frac (1) (3)) \ left (2 ^ (n) + 2 \ cos (\ frac ((n - 4) \ pi) (3)) \ right)) </Dd> <Dl> <Dd> (n 0) + (n 4) + (n 8) + ⋯ = 1 2 (2 n − 1 + 2 n 2 cos ⁡ n π 4) (\ displaystyle (\ binom (n) (0)) + (\ binom (n) (4)) + (\ binom (n) (8)) + \ cdots = (\ frac (1) (2)) \ left (2 ^ (n - 1) + 2 ^ (\ frac (n) (2)) \ cos (\ frac (n \ pi) (4)) \ right)) </Dd> </Dl>

C *( n ) = 10 n + 20