Hello everyone!

Suppose, we have a differential polynomial

**P := u(x) + (D@@2)(u)(x) **

Given this, I am looking for a procedure which gives coefficients depending on the order given as input, for example, lets say, procedure name is **fun_coeff** which depends on** two parameters,** original** polynomial P** and the** order n**, then

**fun_coeff(P, 3) should give [1, 0, 1, 0] **

where each entry corresponds to the coeff of

**[u(x), (D@@1)(u)(x), (D@@2)(u)(x), (D@@3)(u)(x)]**

in the polynomial, similarly

**fun_coeff(P,4) should give [1, 0, 1, 0, 0]**

corresponding to

**[u(x), (D@@1)(u)(x), (D@@2)(u)(x), (D@@3)(u)(x), ****(D@@4)(u)(x)** ]

Thank you all for your time :)