Tribonacci Series

Generate Tribonacci series (each term is sum of previous three).

Logic BuildingIntermediate
Logic Building
# Take n
n = int(input("Enter number of terms: "))

# Generate Tribonacci
if n <= 0:
    print("Invalid input")
elif n == 1:
    print("0")
elif n == 2:
    print("0 1")
elif n == 3:
    print("0 1 1")
else:
    a, b, c = 0, 1, 1
    print(a, b, c, end=" ")
    for i in range(3, n):
        d = a + b + c
        print(d, end=" ")
        a, b, c = b, c, d
    print()

Output

Enter number of terms: 8
0 1 1 2 4 7 13 24

Each term is sum of previous three.

Key Concepts:

  • Start with 0, 1, 1
  • Each next = sum of previous three
  • Track last three terms