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v[1] = 0; v[2] = 2; v[3] = 4; v[4] = 10 + 4*x; for(n = 4, N, my(i = n + 1); v[i] = -x^2*v[i - 4] - 4*x*v[i - 3] - (4 - 2*x)*v[i - 2] + 4*v[i - 1]); 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-801895951aa20f29","steps":["Veronese 2 (j=1)","x \u21a6 x+1"],"edges":["e-274dee66a9035b75","e-4a37d141fad089d8"],"text":"A103406 \u2192 Veronese 2 (j=1) \u2192 x \u21a6 x+1"},"headline":"A103406 \u2192 Veronese 2 (j=1) \u2192 x \u21a6 x+1","chain":null}