219965

Appears in sequences

• Numbers n such that n = p + q with n*p*q = primorial number (A002110) (p <= q, p > 0, q > 0).at n=22A057035
• Irregular triangular array: every periodic simple continued fraction CF represents a quadratic irrational (c + f*sqrt(d))/b, where b,c,f,d are integers and d is squarefree. Row n of this array shows the distinct values of d as CF ranges through the periodic continued fractions having period an n-tuple of 1s and 3s.at n=50A246922