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v[1] = 1; for(n = 2, N, my(i = n); v[i] = (-(8*n^2 - 16*n + 6 + (6*n^2 - 12*n + 6)*x)*v[i - 1] - ((16*n - 12)*x - (4*n - 3)*x^2)*deriv(v[i - 1], x))/(-2*n^2 + n)); 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}},{"oeis_id":"A280580","target":"triangle","first_row":1,"oeis_offset":0,"reversed":false,"trim_zeros":"none","regular_triangle":true,"rows_shown":10,"polytool_commit":"c48629374597092cc41ef4d6273f37991516f984","triangle_example":"Triangle begins:\n  0:    1;\n  1:    1,      1;\n  2:    2,      6,       1;\n  3:    5,     30,      15,       1;\n  4:   14,    140,     140,      28,       1;\n  5:   42,    630,    1050,     420,      45,      1;\n  6:  132,   2772,    6930,    4620,     990,     66,     1;\n  7:  429,  12012,   42042,   42042,   15015,   2002,    91,    1;\n  8: 1430,  51480,  240240,  336336,  180180,  40040,  3640,  120,   1;\n  9: 4862, 218790, 1312740, 2450448, 1837836, 612612, 92820, 6120, 153, 1;\n","recurrence_sentence":"The row polynomials satisfy -(2*n^2+3*n+1)*P(n,x) = -(8*n^2-2+6*n^2*x)*P(n-1,x) - ((16*n+4)*x-(4*n+1)*x^2)*d/dx P(n-1,x) for n >= 1, with P(0,x) = 1.","mathematica":"P[0, x_] := 1;\nP[n_, x_] := P[n, x] = Expand[Together[(-(8*n^2 - 2 + 6*n^2*x)*P[n - 1, x] - ((16*n + 4)*x - (4*n + 1)*x^2)*D[P[n - 1, x], x])/(-2*n^2 - 3*n - 1)]];\nTable[PadRight[CoefficientList[P[n, x], x], n + 1], {n, 0, 9}] // Flatten","pari":"P(N) = {my(v = vector(N + 1)); 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