Monthly Archives: October 2012

Happy Halloween! Time for Vampire Num3ers (including a puzzle)

Definition: http://mathworld.wolfram.com/VampireNumber.html A number   v = x * y   with an even number of digits formed by multiplying a pair of n/2-digit numbers (where the digits are taken from the original number in any order)   x   … Continue reading

Posted in Math Beauty, Number Puzzles | Tagged | 1 Comment

Num3er 36

The factors of   36   are:     1   2   3   4   6   9   12   18   36 The prime factors are:     2 * 2 * 3 * 3     36 … Continue reading

Posted in Math Beauty | Tagged , | 1 Comment

Num3er 159

The factors of   159   are:        1   3   53   159 The prime factors are:     3 * 53   Using each of 9 digits 1-9 once: 159   *   48   =   7632 … Continue reading

Num3er 100001

Goal:   To find positive integers   a, b, c, d, e   so that 1^2   +   a^2   +   b^2   =   c^2   +   d^2   +   e^2,   and 1   … Continue reading

In how many ways x + y + z = 1000

In how many ways can you make sums of three distinct positive integers total (a)   24 (b)   25 (c)   1000 For example, 1 + 2 + 21 = 24,    1 + 2 + 997 = 1000, … Continue reading

Posted in Math Beauty, Number Puzzles | Tagged | 3 Comments

Patterns: Num3ers of the form 1001, 110011, …

My focus:   To examine numbers of the form,   1001, 110011, 11100111, 1111001111, … and to replace the middle two digits (00) with the prime numbers 11 and 13 For example: (1)   1001   =   7 * … Continue reading

Num3er 10001

Goal:   To find positive integers   a, b, c, d, e   so that 1^2   +   a^2   +   b^2   =   c^2   +   d^2   +   e^2,   (sum of three … Continue reading

Num3er 1001

Goal:   To find positive integers   a, b, c, d, e   so that 1^2   +   a^2   +   b^2   =   1001   =   c^2   +   d^2   +   e^2, … Continue reading