This problem was given out at the 2008 Santa Clara Valley Mathematics Field Day competition.
A triangular number, Tn = 1+2+3+ ... + n. There are some triangular numbers which are the products of three consecutive positive integers. For example, T3 = 1+2+3 = 1*2*3. Also, T22736 = 1+2+3+...+22736 = 636*637*638 = 258474216. NOTE: 258474216 is the largest of these numbers.
It turns out that there are exactly six triangular numbers which are the products of three consecutive integers.
Write a program that fills in the following table where TFTN# represents the index of the "Three Factors of Triangular Numbers." They are labeled A through F since they don't correspond to the indexes you will need to get the sums and products.
Your function should return a list containing six lists of three elements. It should be of the form: ((3 1 6) ... (22736 636 258474216)) where the first number in each triplet is the n in 1+2+...+n, the second number is the FIRST number in x(x+1)(x+2), and the last number is the triangular number.
The Three Factors | Triangular Number | Notation | ||||||
TFTN# | 1st | 2nd | 3rd | |||||
---|---|---|---|---|---|---|---|---|
A |
1 |
2 |
3 |
Π= |
6 |
= |
T |
3 |
B |
Π= |
|||||||
C |
Π= |
|||||||
D |
Π= |
|||||||
E |
Π= |
|||||||
F |
636 |
637 |
638 |
Π= |
258474216 |
= |
T |
22736 |