Given a number **N**, the task is to find the sum of the below series till N terms.

**Examples:**

Input:N = 10Output:2.133256Explanation:

The sum of series 1 + 1/3 + 1/5 + 1/7 + 1/9 + 1/11 is 2.133256.Input:N = 20Output:2.479674Explanation:

The sum of series 1 + 1/3 + 1/5 + 1/7 + … + 1/41 is 2.479674.

**Approach:** From the given series, find the formula for Nth term:

1st term = 1 2nd term = 1/3 3rd term = 1/5 4th term = 1/7 . . Nthe term = 1 / (2 * N - 1))

Therefore:

Nth term of the series*** QuickLaTeX cannot compile formula: *** Error message: Error: Nothing to show, formula is empty

Then iterate over numbers in the range **[1, N]** to find all the terms using the above formula and compute their sum.

Below is the implementation of the above approach:

## C++

`// C++ program to find the sum of the` `// series 1 + 1/3 + 1/5 + ...` `#include <iostream>` `using` `namespace` `std;` `// Function to find the sum of the` `// given series` `void` `printSumSeries(` `int` `N)` `{` ` ` `// Intialise the sum to 0` ` ` `float` `sum = 0;` ` ` `for` `(` `int` `i = 1; i <= N; i++) {` ` ` `// Generate the ith term and` ` ` `// add it to the sum` ` ` `sum += 1.0 / (2 * i - 1);` ` ` `}` ` ` `// Print the final sum` ` ` `cout << sum << endl;` `}` `// Driver Code` `int` `main()` `{` ` ` `int` `N = 6;` ` ` `printSumSeries(N);` ` ` `return` `0;` `}` |

## Java

`// Java program to find the sum of the` `// series 1 + 1/3 + 1/5 + ...` `class` `GFG {` ` ` ` ` `// Function to find the sum of the` ` ` `// given series` ` ` `static` `void` `printSumSeries(` `int` `N)` ` ` `{` ` ` `// Intialise the sum to 0` ` ` `float` `sum = ` `0` `;` ` ` ` ` `for` `(` `int` `i = ` `1` `; i <= N; i++) {` ` ` ` ` `// Generate the ith term and` ` ` `// add it to the sum` ` ` `sum += ` `1.0` `/ (` `2` `* i - ` `1` `);` ` ` `}` ` ` ` ` `// Print the final sum` ` ` `System.out.println(sum);` ` ` `}` ` ` ` ` `// Driver Code` ` ` `public` `static` `void` `main (String[] args)` ` ` `{` ` ` `int` `N = ` `6` `;` ` ` ` ` `printSumSeries(N);` ` ` `}` ` ` `}` `// This code is contributed by AnkitRai01` |

## Python3

`# Python3 program to find the sum of the` `# series 1 + 1/3 + 1/5 + ...` `# Function to find the sum of the` `# given series` `def` `printSumSeries(N) :` ` ` `# Intialise the sum to 0` ` ` `sum` `=` `0` `;` ` ` `for` `i ` `in` `range` `(` `1` `, N ` `+` `1` `) :` ` ` `# Generate the ith term and` ` ` `# add it to the sum` ` ` `sum` `+` `=` `1.0` `/` `(` `2` `*` `i ` `-` `1` `);` ` ` `# Print the final sum` ` ` `print` `(` `sum` `);` `# Driver Code` `if` `__name__ ` `=` `=` `"__main__"` `:` ` ` `N ` `=` `6` `;` ` ` `printSumSeries(N);` `# This code is contributed by AnkitRai01` |

## C#

`// C# program to find the sum of the` `// series 1 + 1/3 + 1/5 + ...` `using` `System;` `class` `GFG {` ` ` ` ` `// Function to find the sum of the` ` ` `// given series` ` ` `static` `void` `printSumSeries(` `int` `N)` ` ` `{` ` ` `// Intialise the sum to 0` ` ` `float` `sum = 0;` ` ` ` ` `for` `(` `int` `i = 1; i <= N; i++) {` ` ` ` ` `// Generate the ith term and` ` ` `// add it to the sum` ` ` `sum += (` `float` `)1.0 / (2 * i - 1);` ` ` `}` ` ` ` ` `// Print the final sum` ` ` `Console.WriteLine(sum);` ` ` `}` ` ` ` ` `// Driver Code` ` ` `public` `static` `void` `Main (` `string` `[] args)` ` ` `{` ` ` `int` `N = 6;` ` ` ` ` `printSumSeries(N);` ` ` `} ` `}` `// This code is contributed by AnkitRai01` |

## Javascript

`<script>` `// javascript program to find the sum of the` `// series 1 + 1/3 + 1/5 + ...` `// Function to find the sum of the` `// given series` `function` `printSumSeries( N)` `{` ` ` `// Intialise the sum to 0` ` ` `let sum = 0;` ` ` `for` `(let i = 1; i <= N; i++) {` ` ` `// Generate the ith term and` ` ` `// add it to the sum` ` ` `sum += 1.0 / (2 * i - 1);` ` ` `}` ` ` `// Print the final sum` ` ` `document.write(sum.toFixed(5));` `}` `// Driver Code` ` ` `let N = 6;` ` ` `printSumSeries(N);` ` ` `// This code is contributed by todaysgaurav` `</script>` |

**Output:**

1.87821

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