42106

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 45.at n=3A031633
• Numbers k > 1 such that, in base 5, k and k^2 contain the same digits in the same proportion.at n=12A061659
• Number of zig-zag paths from top to bottom of a rectangle of width 10 with n rows.at n=13A153360
• a(n) is the least m such that A341284(m) = 2*n*prime(m+1) - prime(m).at n=52A342027