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v[1] = 1; v[2] = 1; v[3] = x + x^2; for(n = 3, N, my(i = n + 1); v[i] = ((n - 2)*x^2*v[i - 2])/(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-ddd13fb19530ec39","steps":[],"edges":[],"text":"A133081"},"headline":"A133081: An interpolation operator, companion to A133080.","chain":null}