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You are here.... Solve the Da Vinci Code .... Patterns .... Challenge 1 of 6

When you complete the six challenges in this section you will be given the first part of the secret password to enable you to take part in the mission. The second part of the password is at the end of the Codes section. Good luck.

Now let us learn about some patterns or sequences using numbers. The first pattern forms a triangle.

Triangular Numbers

  • Numbers which can be arranged in a compact triangular pattern are termed as triangular numbers
  • The triangular numbers are formed by partial sum of the series 1+2+3+4+5+6+7......+n. So
    1st Triangular Number = 1
    2nd Triangular Number = 1 + 2 = 3
    3rd Triangular Number = 1 + 2 + 3 = 6
    4th Triangular Number = 1 + 2 + 3 + 4 = 10
  • Any triangular number can be worked out in two ways. For example to find the 6th Triangular Number you could add 1 + 2 + 3 + 4 + 5 + 6 = 21. Or you could multiply 6 by the number which follows it 7 and then divide it in half. 6 X 7 ÷ 2 = 21. (This is like getting the half of a rectangle, which of course is a triangle as you can see in the diagram below.

  • Challenge 1: Find the 14th triangular number and enter it as the password below in the box below the flashing lights to move to the next section. Then click on the "Login" Button or press the ENTER key on your keyboard. Good Luck!
  • Use our calculator if you need help.