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v[1] = -1 + x; for(n = 1, N, my(i = n + 1); v[i] = (-(4*n^2 + 2*n - (4*n + 1)*x + x^2)*v[i - 1])/(2*n - 1 - x)); 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-4f6e747b794bcc2e","steps":["x \u21a6 \u2212x+1","P\u2099 + P\u2099\u208a\u2081"],"edges":["e-8b470702f19ec444","e-769dd7c64d51b4a5"],"text":"A028338 \u2192 x \u21a6 \u2212x+1 \u2192 P\u2099 + P\u2099\u208a\u2081"},"headline":"A028338 \u2192 x \u21a6 \u2212x+1 \u2192 P\u2099 + P\u2099\u208a\u2081","chain":null}