Revision Notes for Class 6 Maths Chapter 1: Patterns in Mathematics

Quick revision notes summarising all key number and shape sequences from Class 6 Maths Chapter 1 “Patterns in Mathematics”. These Class 6 Mathematics Chapter 1 notes are ideal for quick revision just before exams.

• Counting numbers: 1,2,3,4,… (add 1 each time).
• Odd numbers: 1,3,5,7,… and even numbers: 2,4,6,8,… (add 2 each time).
• Triangular numbers: 1,3,6,10,15,… — nth term = n(n+1)/2.
• Square numbers: 1,4,9,16,25,… — nth term = n².
• Cube numbers: 1,8,27,64,125,… — nth term = n³.
• Virahanka numbers: 1,2,3,5,8,13,21,… — each term is the sum of the two before it.
• Powers of 2: 1,2,4,8,16,… and powers of 3: 1,3,9,27,81,… — each term is double (or triple) the previous one.
• Hexagonal numbers: 1,7,19,37,61,… — equal to 6×(triangular number)+1.
• Key identities: sum of first n odd numbers = n²; sum of two consecutive triangular numbers = a square number; sum of first n cubes = (sum of first n counting numbers)² (Nicomachus’s theorem); adding up powers of 2 and then adding 1 gives the next power of 2.
• Complete graph with n points has n(n-1)/2 connecting lines — always a triangular number.
• Koch snowflake: the number of line segments multiplies by 4 at every step (3, 12, 48, 192, … = 3×4ⁿ).

See also: NCERT Solutions for Class 6 Maths Chapter 1

Practice more: Extra Questions for Class 6 Maths Chapter 1

For the full chapter, see the Class 6 Maths Formulas Handbook.

Written by Satish

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