Download Squares Primes Cube Triangular Numbers

Key sequences of numbers The following sequences of numbers are very important, you must learn them.
1. Prime numbers: A prime number is a number that has ONLY TWO FACTORS!
The sequence of prime numbers is:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41.....
REMEMBER: 1 is not a prime number.
The only even prime number is 2.
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2. Square numbers: a square number is a number you get when you multiply another number by itself.
e.g 22 = 2 x 2 = 4 so 4 is a square number
72 = 7 x 7 = 49 so 49 is a square number
2
is the symbol for squaring a number
The sequence of square numbers is:
1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144.....
Also: the number you multiplied by itself is called the square root. so 7 is the square root of 49. 6 is the square root of 36.....
√
This is the symbol for square root
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Cube Numbers A cube number is what you get when you multiply another number BY ITSELF 3 TIMES.
e.g 5 x 5 x 5 = 125 so 125 is a cube number (5 is the cube root)
4 x 4 x 4 = 64 so 64 is a cube number
the list of cube numbers is: 1, 8, 27, 64, 125, 216.......
3
is the symbol for cubing a number
∛ is the symbol for a cube root
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3. Triangular numbers:
The sequence of triangular numbers is:
1 , 3 , 6 , 10 , 15 , 21 , 28.....
+2 +3 +4 +5 +6 +7
Why are they called triangular numbers?
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+2
+3
+4
+5
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