-17920

Appears in sequences

• sin(tan(x)-tanh(x))=4/3!*x^3+544/7!*x^7-17920/9!*x^9+707584/11!*x^11...at n=3A013452
• Expansion of e.g.f.: exp(arctan(x)-arctanh(x))=1-4/3!*x^3+160/6!*x^6-1440/7!*x^7...at n=9A013462
• Triangular array of the coefficients of the sequence of Abel polynomials A(n,x) := x*(x-n)^(n-1).at n=41A137452
• A triangular sequence from an expansion of coefficients of the function: p(x,t)=Exp(x*g*(t))*(1-f(t)^2);f(t)=4/(t^4-1);g(t)=t. (based on the Weierstrass functions of Scherk's minimal surface).at n=40A137520
• Triangle T(n, k) = coefficients of p(n, x), where p(n, x) = (-1)^n*(x+2-n)*(x+2)^(n-1), p(0, x) = 1, and p(1, x) = -1-x, read by rows.at n=56A158285
• Irregular triangle read by rows: T(n,m) = coefficients in a power/Fourier series expansion of an arbitrary anharmonic oscillator's exact phase space trajectory.at n=39A276738
• Irregular triangle read by rows T(n,m), coefficients in power/Fourier series expansion of an arbitrary anharmonic oscillator's exact differential time dependence.at n=24A276815
• T(n, k) = 2^n * n! * [x^k] [z^n] (4*exp(x*z))/(exp(z) + 1)^2, triangle read by rows, for 0 <= k <= n. Coefficients of Euler polynomials of order 2.at n=40A326480