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v[1] = 2 + x; for(n = 2, N, my(i = n); v[i] = (1 + x)*v[i - 1] + x*deriv(v[i - 1], 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-3cb22164e2f83fe1","steps":["P\u2099 + P\u2099\u208a\u2081"],"edges":["e-3851164db8045998"],"text":"A008277 \u2192 P\u2099 + P\u2099\u208a\u2081"},"headline":"A008277 \u2192 P\u2099 + P\u2099\u208a\u2081","chain":null}