Cache update: 60 minutes

Problems Archives

The problems archives table shows problems 1 to 699. If you would like to tackle the 10 most recently published problems then go to Recent problems.
Click the description/title of the problem to view details and submit your answer.


IDDescription / TitleSolved By
101Optimum polynomial
10363
102Triangle containment
20361
103Special subset sums: optimum
7228
104Pandigital Fibonacci ends
15005
105Special subset sums: testing
7225
106Special subset sums: meta-testing
5746
107Minimal network
10055
108Diophantine reciprocals I
11659
109Darts
7380
110Diophantine reciprocals II
7357
111Primes with runs
6504
112Bouncy numbers
23002
113Non-bouncy numbers
10172
114Counting block combinations I
9919
115Counting block combinations II
9049
116Red, green or blue tiles
11131
117Red, green, and blue tiles
10200
118Pandigital prime sets
6210
119Digit power sum
11367
120Square remainders
12753
121Disc game prize fund
8895
122Efficient exponentiation
7050
123Prime square remainders
10624
124Ordered radicals
12694
125Palindromic sums
12506
126Cuboid layers
4208
127abc-hits
5600
128Hexagonal tile differences
4468
129Repunit divisibility
5674
130Composites with prime repunit property
5333
131Prime cube partnership
6682
132Large repunit factors
5738
133Repunit nonfactors
4967
134Prime pair connection
6328
135Same differences
5752
136Singleton difference
5053
137Fibonacci golden nuggets
4920
138Special isosceles triangles
5219
139Pythagorean tiles
5053
140Modified Fibonacci golden nuggets
3857
141Investigating progressive numbers, n, which are also square
3470
142Perfect Square Collection
5253
143Investigating the Torricelli point of a triangle
2425
144Investigating multiple reflections of a laser beam
5630
145How many reversible numbers are there below one-billion?
15465
146Investigating a Prime Pattern
4491
147Rectangles in cross-hatched grids
2680
148Exploring Pascal's triangle
4632
149Searching for a maximum-sum subsequence
4361
150Searching a triangular array for a sub-triangle having minimum-sum
3568