20525

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 15.at n=14A031603
• House numbers: a(n) = (n+1)^3 + Sum_{i=1..n} i^2.at n=24A051662
• Numbers k such that 3*2^k - 7 is prime.at n=35A059747
• Number of ordinary double points of a family of threefolds.at n=13A294604
• Number of noncrossing path sets on n nodes up to rotation and reflection with each path having at least two nodes.at n=12A303839