# Tag Archives: series

## k-th number in the Odd-Even sequenceNovember 15, 2017

Given two numbers n and k, find the k-th number in the Odd-Even sequence made of n. The Odd-Even sequence contains first contains all odd… Read More »

## Find n-th term in the series 7, 15, 32, …November 3, 2017

Given a series 7, 15, 32, …… Find the nth term of this series. Examples : Input : 5 Output : 138 Input : 7… Read More »

## Find n-th term in sequence 1, 1, 2, 1, 2, 3, 1, 2, 3, 4, ….

Consider the infinite sequence of integers: 1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5…. The sequence is built… Read More »

## Find n-th term in the series 9, 33, 73,129 …October 30, 2017

Given a series 9, 33, 73, 129… Find the n-th term of the series. Examples: Input : n = 4 Output : 129 Input :… Read More »

## Program for harmonic mean of numbersOctober 28, 2017

Given an array of elements, find harmonic mean of numbers. Examples: Input : arr[] = {2.0, 1.0} Output : 1.3333 Harmonic mean = 2/(1/2.0 +… Read More »

## Sum of multiples of a number up to NOctober 26, 2017

Given a number a and limit N. Find the sum of multiple of a upto N. Examples: Input : a = 4, N = 23… Read More »

## First collision point of two seriesOctober 24, 2017

Given five numbers a, b, c, d and n (where a, b, c, d, n > 0). These values represent n terms of two series.… Read More »

## Armstrong Numbers between two integersOctober 23, 2017

A positive integer with digits a, b, c, d… is called an Armstrong number of order n if following condition is satisfied. abcd… = an… Read More »

## Pierpont PrimeOctober 20, 2017

A Pierpont Prime is a prime number of the form p = 2l.3k + 1. First few Pierpont prime numbers are 2, 3, 5, 7,… Read More »

## Woodall Number

A Woodall number is of the form: Wn = n.2n – 1 The first few Woodall numbers are: 1, 7, 23, 63, 159, 383, 895……… Read More »

## Leonardo NumberOctober 18, 2017

The Leonardo numbers are a sequence of numbers given by the recurrence: The first few Leonardo Numbers are 1, 1, 3, 5, 9, 15, 25,… Read More »

## Vampire NumberOctober 12, 2017

Introduction to Vampire Number and its implementation using python. Introduction In mathematics, a vampire number (or true vampire number) is a composite natural number v,… Read More »

## Happy NumbersOctober 10, 2017

A Happy Number n is defined by the following process. Starting with n, replace it with the sum of the squares of its digits, and… Read More »

## Program to find Sum of a Series a^1/1! + a^2/2! + a^3/3! + a^4/4! +…….+ a^n/n!October 9, 2017

Given two values ‘a’ and ‘n’, find sum of series a^1/1! + a^2/2! + a^3/3! + a^4/4! +…….+ a^n/n!. Input : a = 2 and… Read More »

## Spy Number (Sum and Products of Digits are same)October 7, 2017

A number is said to be a Spy number if the sum of all the digits is equal to the product of all digits. Examples:… Read More »