A bizarre "Rule of Four" has been identified in the basic structure of the majority of inorganic materials—and scientists are stumped as to why. The pattern is found in the so-called "unit cell" of ...

You can violate the pattern day trader (PDT) rules without realizing it. The consequences for violating PDT vary, but can be inconvenient for investors who are not actively trading. For active ...

Logical reasoning IQ-based puzzles test your ability to analyse patterns, deduce relationships, and apply rules to reach correct conclusions. They include sequences, syllogisms, matrix problems, ...

You will need to be confident with arithmetic sequences and the 𝑛th term rule to understand these other types of sequences. A geometric sequence contains numbers that are multiplied by a certain ...