21741

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 98.at n=35A031596
• Number of prime pairs below 10^n having a difference of 30.at n=6A093750
• Total Wiener index of star-like trees with n edges.at n=12A186310
• Number of (n+1)X(2+1) 0..1 arrays x(i,j) with row sums sum{j^3*x(i,j), j=1..2+1} nondecreasing, and column sums sum{i^3*x(i,j), i=1..n+1} nondecreasing.at n=10A232855
• a(n) = 2^(n+2) + 3^n + 10.at n=9A254365
• Number of induced paths in the n-ladder graph P_2 X P_n.at n=14A360201
• E.g.f. A(x) satisfies A(x) = exp(x*C(x*A(x))^2), where C(x) = 1 + x*C(x)^2 is the g.f. of A000108.at n=5A382032
• G.f. satisfies A(x) = A(x^3)/(A(x^2) - A(x^3)), with A(0) = 0, A'(0) = 1.at n=61A382317