Given a number and we have to check whether it is a Fibonacci number or not in Python?

给定一个数字，我们必须检查Python中是否为斐波那契数字 ？

检查斐波那契数 (Checking Fibonacci number)

Consider the given Fibonacci series with a first few terms: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, and so on...

考虑给定斐波那契数列的前几个术语： 0、1、1、2、3、5、8、13、21、34、55、89、144，依此类推...

There is a popular formula to check whether a given number is a Fibonacci number or not? (5*n² + 4) or (5*n² – 4)

有一个流行的公式可以检查给定的数字是否为斐波那契数 ？ (5 * n ² + 4)或(5 * n ² – 4)

If the result of this formula is a perfect square then the number will be a Fibonacci number.

如果此公式的结果是一个完美的平方，则该数字将是斐波那契数。

Example:

例：

    Input:
num = 13
Output:
Yes, 13 is a Fibonacci number
Input:
num = 143
Output:
No, 144 is not a Fibonacci number

Python程序检查斐波那契数 (Python program to check Fibonacci number)

# python program to check if given
# number is a Fibonacci number
import math
# function to check perferct square
def checkPerfectSquare(n):
sqrt = int(math.sqrt(n))
if pow(sqrt, 2) == n:
return True
else:
return False
# function to check  Fibonacci number
def isFibonacciNumber(n):
res1 = 5 * n * n + 4
res2 = 5 * n * n - 4
if checkPerfectSquare(res1) or checkPerfectSquare(res2):
return True
else:
return False
# main code
num = int(input("Enter an integer number: "))
# checking
if isFibonacciNumber(num):
print ("Yes,", num, "is a Fibonacci number")
else:
print ("No,", num, "is not a Fibonacci number")

Output

输出量

First run:
Enter an integer number: 13
Yes, 13 is a Fibonacci number
Second run:
Enter an integer number: 144
Yes, 144 is a Fibonacci number
Third run:
Enter an integer number: 143
No, 143 is not a Fibonacci number

翻译自: https://www.includehelp.com/python/check-whether-a-given-number-is-a-fibonacci-number-or-not.aspx