22719

Appears in sequences

• Semiprimes q such that q^2-4 and q^2+4 are also semiprimes.at n=20A173084
• Values x for records of the minima of the positive distance d between the ninth power of a positive integer x and the square of an integer y such that d = x^9 - y^2 (x <> k^2 and y <> k^9).at n=27A179791
• Odd numbers n divisible by 3 such that for all k >= 1 the numbers n*2^k - 1 and n*2^(k+1) - 1 do not form a pair of primes.at n=2A243858
• a(n) is the number of sets modulo n which can be formed by a finite arithmetic sequence.at n=36A331503
• Number of losing integer partitions of n in the impartial combinatorial game LCTR (left column, top row).at n=41A373457