21607465

Appears in sequences

• Numerators of coefficients of 1/2^(2n+1) in Newton's series for Pi.at n=19A054387
• The powerfree part of the central binomial coefficients.at n=33A056060
• Numerator of (-1/3)^n*sqrt(Pi)/(Gamma(1/2 - n)*Gamma(1 + n)).at n=17A285019