53945

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 42.at n=6A031630
• Numbers having four 8's in base 9.at n=9A043488
• Number of n X n binary arrays symmetric under 90-degree rotation with all ones connected only in a zee 1,1 1,2 2,2 2,3 in any orientation.at n=12A145958
• a(n) = 74*n^2 - 1.at n=26A158744
• Expansion of g.f. A(x) satisfying A(x) = 1 + x*A(x)/(1 - 4*x*A(x))^2.at n=6A365774