Similar to 四つ子素数

Fibonacci word

Fermat number

Weird number

Deficient number

Practical number

Blum integer

Friedman number

Brocard's problem

Partition function (number theory)

Square-free integer

Square triangular number

Square number

Heegner number

Perrin number

Bell number

Pell number

Bernoulli number

Markov number

Mian–Chowla sequence

Divisor

Amicable numbers

Good prime

Lychrel number