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The smallest unresolved non-prime order to Lam's Problem.

No number of even 10 digits can be a no-rep emirp. [Dale]

1¹ + 2² + 3³ + 4⁴ + 5⁵ + 6⁶ + 7⁷ + 8⁸ + 9⁹ + 10¹⁰ is prime. [Kulsha]

There exists a polynomial in 10 variables with integer coefficients such that the set of primes equals the set of positive values of this polynomial obtained as the variables run through all nonnegative integers. [Ribenboim]

If the number of the month and the number of the day are relatively prime, then June has the fewest such days ... 10.

The smallest number which is the sum of two odd primes in two ways (10 = 3 + 7 = 5 + 5).

There are 10 non-twin primes less than 10². [Francis]

The 10-bit number (1110101001) containing zeros on prime positions and units on non-prime positions, reading right-to-left, is a binary emirp. [Kulsha]

There are exactly 10 palindromic mountain primes. [Kulsha]

10! - 9! + 8! - 7! + 6! - 5! + 4! - 3! + 2! - 1! is prime. [Poo Sung]

The smallest composite number (the fifth one) which is smaller than the corresponding (the fifth) prime 11. [Murthy]

The only number with the property that the sum as well as the difference of its prime divisors are primes (2 + 5 = 7 and 5 - 2 = 3). [Murthy]

(10!)² + 1 is prime. [Dobb]

The Top 10 is a catalogue of primal configurations by Rudolf Ondrejka.

The smallest even number whose square is the sum of n first primes. [Gallardo]

10! = 3! 5! 7! Note the first three consecutive odd primes. [Capelle]

10 ones plus 10 is prime. This is the smallest such two-digit number. [Opao]

10! + 11 and 10! - 11 are primes. [Patterson]

10 is the only number n such that n^2 = prime(2*n) + prime(n). [Firoozbakht]

The largest number N such that any set of N consecutive integers contains at least one integer relatively prime to all other integers in the set. [Rupinski]

(10) = prime(1!) + prime(0!) [Firoozbakht]

The number of known perfect powers n with no primes between n and the next larger perfect power. [Capelle]

The smallest reflectable semiprime and also the smallest reflectable brilliant number. [Capelle]