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v[1] = x; for(n = 2, N, my(i = n); v[i] = (-(4*n^2 - 10*n + 6 - (4*n - 5)*x + x^2)*v[i - 1])/(2*n - 4 - x)); v};\nrow(n, p) = {my(c = Vecrev(p)); c};\nT(N) = {my(v = P(N)); concat(vector(#v, i, row(i, v[i])))};\nT(10)","reading":{"first_row":1,"offset":1,"reversed":false,"trim_zeros":"none","regular_triangle":false}}],"derivation":{"root":"n-4f6e747b794bcc2e","steps":["x \u21a6 \u2212x (shift -1)","P\u2099 + P\u2099\u208a\u2081"],"edges":["e-d7c9e146299b18aa","e-557516b36262f3b9"],"text":"A028338 \u2192 x \u21a6 \u2212x (shift -1) \u2192 P\u2099 + P\u2099\u208a\u2081"},"headline":"A028338 \u2192 x \u21a6 \u2212x (shift -1) \u2192 P\u2099 + P\u2099\u208a\u2081","chain":null}