20913

Appears in sequences

• tanh(arcsin(arctanh(x)))=x+1/3!*x^3+9/5!*x^5+281/7!*x^7+20913/9!*x^9...at n=4A012141
• 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 96.at n=32A031594
• Numbers whose base-12 representation has exactly 5 runs.at n=19A043654
• G.f.: A(x) = 1+x*(1+x*(1+x*(...(1+x*(...)^n)...)^3)^2)^1.at n=8A095793
• G.f. satisfies A(x) = 1 + x*A(x)^2 + x^3*A(x)^5.at n=9A216490
• Numbers x such that sigma(x) + sigma(R(x)) = sigma(x + R(x)), where R(x) is the digit reversal of x and sigma(x) is the sum of the divisors of x.at n=21A246487
• Number of partitions of n into 8 or more parts.at n=30A347544