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Problems Archives

The problems archives table shows problems 1 to 670. 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
201Subsets with a unique sum
1963
202Laserbeam
2158
203Squarefree Binomial Coefficients
8178
204Generalised Hamming Numbers
6513
205Dice Game
13402
206Concealed Square
21810
207Integer partition equations
4227
208Robot Walks
1505
209Circular Logic
2170
210Obtuse Angled Triangles
1471
211Divisor Square Sum
3651
212Combined Volume of Cuboids
1178
213Flea Circus
2008
214Totient Chains
4592
215Crack-free Walls
3264
216Investigating the primality of numbers of the form 2n2-1
3544
217Balanced Numbers
1293
218Perfect right-angled triangles
2685
219Skew-cost coding
1291
220Heighway Dragon
1954
221Alexandrian Integers
1801
222Sphere Packing
1823
223Almost right-angled triangles I
1280
224Almost right-angled triangles II
1028
225Tribonacci non-divisors
3954
226A Scoop of Blancmange
1520
227The Chase
1813
228Minkowski Sums
1143
229Four Representations using Squares
1280
230Fibonacci Words
2539
231The prime factorisation of binomial coefficients
4813
232The Race
1522
233Lattice points on a circle
1935
234Semidivisible numbers
2894
235An Arithmetic Geometric sequence
4454
236Luxury Hampers
794
237Tours on a 4 x n playing board
1346
238Infinite string tour
819
239Twenty-two Foolish Primes
1568
240Top Dice
1897
241Perfection Quotients
774
242Odd Triplets
885
243Resilience
8456
244Sliders
1105
245Coresilience
698
246Tangents to an ellipse
673
247Squares under a hyperbola
1261
248Numbers for which Euler’s totient function equals 13!
1109
249Prime Subset Sums
2220
250250250
2591