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v[1] = 0; v[2] = 0; v[3] = 1; for(n = 3, N, my(i = n + 1); v[i] = ((3*n - 7 + (2*n - 6)*x)*v[i - 1] - (5 + 9*x + 4*x^2)*deriv(v[i - 1], x))/(n - 2)); v};\nrow(n, p) = {my(c = Vecrev(p)); c};\nT(N) = {my(v = P(N)); concat(vector(#v, i, row(i - 1, v[i])))};\nT(9)","reading":{"first_row":0,"offset":0,"reversed":false,"trim_zeros":"none","regular_triangle":false}}],"derivation":{"root":"n-75ccd0453a9b6cec","steps":["basis A007318","D"],"edges":["e-2a29a8b9938e2bd7","e-44388154107108dc"],"text":"A011973 \u2192 basis A007318 \u2192 D"},"headline":"A011973 \u2192 basis A007318 \u2192 D","chain":null}