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Craven and G. Csordas, Multiplier sequences for fields, Illinois J. Math. 21 (1977); Polya--Schur, Theorem 40 of P. Branden, arXiv:1410.6601: sum_k f(k) x^k / k! = f(theta) e^x = C e^x x^m prod (1 + x/a_j), a_j > 0); f(k) has one sign for k >= 0, so coefficients of one sign stay of one sign; applied to f(n, .) for each n","lean_route":null,"lean_declarations":["RealRooted.isMultiplierSequence_eval_of_roots_nonpos","RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos","RealRooted.isMultiplierSequence_iff_preserves"],"certificate_hash":"81e3aff60622d7c1647b929c41e5d8f45653e5e31beb7ef2e5775de9f951c2c8","verification_polytool":"replayed","verification_lean":"not_attempted","claims":[{"claim":"real_rooted","from_index":0,"region":{"upper":{"closed":true,"value":"0"}}}],"premises":[{"position":0,"node_id":"n-ac04e52510a48bb5","role":"sequence","name":"Triangular array read by rows: row n gives the coefficients of the polynomial p(n,x) defined in Comments.","uses":{"claim":"real_rooted","from_index":0,"region":{"upper":{"closed":true,"value":"0"}}},"uses_text":"Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]"}]}],"used_by":[],"used_by_total":0,"links":[],"oeis":[],"bfiles":[],"oeis_texts":[{"oeis_id":"","target":"node","first_row":0,"oeis_offset":0,"reversed":false,"trim_zeros":"none","regular_triangle":false,"rows_shown":10,"polytool_commit":"c48629374597092cc41ef4d6273f37991516f984","triangle_example":"Triangle begins:\n  0:   1;\n  1:   3,    2;\n  2:   5,    4;\n  3:  11,   14,    3;\n  4:  21,   32,    9;\n  5:  43,   82,   36,   4;\n  6:  85,  188,  102,  16;\n  7: 171,  438,  297,  72,   5;\n  8: 341,  984,  783, 240,  25;\n  9: 683, 2202, 2034, 780, 125, 6;\n","recurrence_sentence":"The row polynomials satisfy (36*n+36+(9*n^2+31*n+22)*x+(n^3+4*n^2+5*n+2)*x^2)*P(n,x) = (180*n+36+(63*n^2+245*n+22)*x+(5*n^3+52*n^2+101*n+2)*x^2+(2*n^3+10*n^2+12*n)*x^3)*P(n-1,x) - (324+(162*n+702)*x+(18*n^2+243*n+554)*x^2+(17*n^2+121*n+190)*x^3+(4*n^2+20*n+24)*x^4)*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[((180*n + 36 + (63*n^2 + 245*n + 22)*x + (5*n^3 + 52*n^2 + 101*n + 2)*x^2 + (2*n^3 + 10*n^2 + 12*n)*x^3)*P[n - 1, x] - (324 + (162*n + 702)*x + (18*n^2 + 243*n + 554)*x^2 + (17*n^2 + 121*n + 190)*x^3 + (4*n^2 + 20*n + 24)*x^4)*D[P[n - 1, x], x])/(36*n + 36 + (9*n^2 + 31*n + 22)*x + (n^3 + 4*n^2 + 5*n + 2)*x^2)]];\nTable[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten","pari":"P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = ((180*n + 36 + (63*n^2 + 245*n + 22)*x + (5*n^3 + 52*n^2 + 101*n + 2)*x^2 + (2*n^3 + 10*n^2 + 12*n)*x^3)*v[i - 1] - (324 + (162*n + 702)*x + (18*n^2 + 243*n + 554)*x^2 + (17*n^2 + 121*n + 190)*x^3 + (4*n^2 + 20*n + 24)*x^4)*deriv(v[i - 1], x))/(36*n + 36 + (9*n^2 + 31*n + 22)*x + (n^3 + 4*n^2 + 5*n + 2)*x^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-75ccd0453a9b6cec","steps":["x \u21a6 x+2 (shift +1)","\u03b8+1"],"edges":["e-7fc1b55fb0aa373a","e-42735f4be786e5b0"],"text":"A011973 \u2192 x \u21a6 x+2 (shift +1) \u2192 \u03b8+1"},"headline":"A011973 \u2192 x \u21a6 x+2 (shift +1) \u2192 \u03b8+1","chain":null}
