# Program to find sum of series 1 + 1/2 + 1/3 + 1/4 + .. + 1/n

If inverse of a sequence follows rule of an A.P i.e, Arithmetic progression, then it is said to be in Harmonic Progression.In general, the terms in a harmonic progression can be denoted as : 1/a, 1/(a + d), 1/(a + 2d), 1/(a + 3d) …. 1/(a + nd).

As Nth term of AP is given as ( a + (n – 1)d) .Hence, Nth term of harmonic progression is reciprocal of Nth term of AP, which is : 1/(a + (n – 1)d)

where “a” is the 1st term of AP and “d” is the common difference.

We can use a for loop to find sum.

Attention reader! All those who say programming isn't for kids, just haven't met the right mentors yet. Join the ** Demo Class for First Step to Coding Course, **specifically **designed for students of class 8 to 12. **

The students will get to learn more about the world of programming in these **free classes** which will definitely help them in making a wise career choice in the future.

## C++

`// C++ program to find sum of series` `#include <iostream>` `using` `namespace` `std;` `// Function to return sum of` `// 1/1 + 1/2 + 1/3 + ..+ 1/n` `class` `gfg` `{` ` ` `public` `: ` `double` `sum(` `int` `n)` `{` ` ` `double` `i, s = 0.0;` ` ` `for` `(i = 1; i <= n; i++)` ` ` `s = s + 1/i;` ` ` `return` `s;` `}` `};` `// Driver code` `int` `main()` `{` ` ` `gfg g;` ` ` `int` `n = 5;` ` ` `cout << ` `"Sum is "` `<< g.sum(n);` ` ` `return` `0;` `}` `// This code is contributed by SoM15242.` |

## C

`// C program to find sum of series` `#include <stdio.h>` `// Function to return sum of 1/1 + 1/2 + 1/3 + ..+ 1/n` `double` `sum(` `int` `n)` `{` ` ` `double` `i, s = 0.0;` ` ` `for` `(i = 1; i <= n; i++)` ` ` `s = s + 1/i;` ` ` `return` `s;` `}` `int` `main()` `{` ` ` `int` `n = 5;` ` ` `printf` `(` `"Sum is %f"` `, sum(n));` ` ` `return` `0;` `}` |

## Java

`// Java Program to find sum of series` `import` `java.io.*;` `class` `GFG {` ` ` ` ` `// Function to return sum of` ` ` `// 1/1 + 1/2 + 1/3 + ..+ 1/n` ` ` `static` `double` `sum(` `int` `n)` ` ` `{` ` ` `double` `i, s = ` `0.0` `;` ` ` `for` `(i = ` `1` `; i <= n; i++)` ` ` `s = s + ` `1` `/i;` ` ` `return` `s;` ` ` `}` ` ` ` ` ` ` `// Driven Program` ` ` `public` `static` `void` `main(String args[])` ` ` `{` ` ` `int` `n = ` `5` `;` ` ` `System.out.printf(` `"Sum is %f"` `, sum(n));` ` ` ` ` `}` `}` `// This code is contributed by Nikita Tiwari.` |

## Python3

`# Python program to find the sum of series` `def` `sum` `(n):` ` ` `i ` `=` `1` ` ` `s ` `=` `0.0` ` ` `for` `i ` `in` `range` `(` `1` `, n` `+` `1` `):` ` ` `s ` `=` `s ` `+` `1` `/` `i;` ` ` `return` `s;` `# Driver Code` `n ` `=` `5` `print` `(` `"Sum is"` `, ` `round` `(` `sum` `(n), ` `6` `))` `# This code is contributed by Chinmoy Lenka` |

## C#

`// C# Program to find sum of series` `using` `System;` `class` `GFG {` ` ` ` ` `// Function to return sum of` ` ` `// 1/1 + 1/2 + 1/3 + ..+ 1/n` ` ` `static` `float` `sum(` `int` `n)` ` ` `{` ` ` `double` `i, s = 0.0;` ` ` ` ` `for` `(i = 1; i <= n; i++)` ` ` `s = s + 1/i;` ` ` ` ` `return` `(` `float` `)s;` ` ` `}` ` ` ` ` `// Driven Program` ` ` `public` `static` `void` `Main()` ` ` `{` ` ` `int` `n = 5;` ` ` ` ` `Console.WriteLine(` `"Sum is "` ` ` `+ sum(n));` ` ` ` ` `}` `}` `// This code is contributed by vt_m.` |

## PHP

`<?php` `// PHP program to find sum of series` `// Function to return sum of` `// 1/1 + 1/2 + 1/3 + ..+ 1/n` `function` `sum( ` `$n` `)` `{` ` ` `$i` `;` ` ` `$s` `= 0.0;` ` ` `for` `(` `$i` `= 1; ` `$i` `<= ` `$n` `; ` `$i` `++)` ` ` `$s` `= ` `$s` `+ 1 / ` `$i` `;` ` ` `return` `$s` `;` `}` ` ` `// Driver Code` ` ` `$n` `= 5;` ` ` `echo` `(` `"Sum is "` `);` ` ` `echo` `(sum(` `$n` `));` ` ` `//This code is contributed by vt_m` `?>` |

## Javascript

`<script>` `// javascript Program to find sum of series` ` ` `// Function to return sum of` `// 1/1 + 1/2 + 1/3 + ..+ 1/n` `function` `sum(n)` `{` ` ` `var` `i, s = 0.0;` ` ` `for` `(i = 1; i <= n; i++)` ` ` `s = s + 1/i;` ` ` `return` `s;` `}` ` ` `// Driven Program` `var` `n = 5;` `document.write(sum(n).toFixed(5));` `// This code is contributed by Amit Katiyar` `</script>` |

**Output:**

2.283333