52609

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 18.at n=21A031606
• Least prime in A031936 (lesser of 18-twins) whose distance to the next 18-twin is 2*n.at n=23A052358
• G.f. satisfies: A(x) = exp( Sum_{n>=1} C(2*n,n)/2 * A(x^n) * x^n/n ).at n=10A199137
• Number of representations of n as a sum of products of distinct pairs of positive integers, considered to be equivalent when terms or factors are reordered.at n=49A211856
• Primes of the form 384*k + 1.at n=36A229854
• Total number of preferential arrangements of 1, 2, ..., n things.at n=6A239914
• Prime numbersat n=5372