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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":"29be83b80f58cb2918d59ecee7217ab26ae52071b07ab8cd0c591c6b9fa6a3f1","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-37ec1285a176250d","role":"sequence","name":"veronese_section_2_0 of Riordan array (1-x,x/(1-x)).","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: 0, 2;\n  1: 0, 2;\n  2: 0, 2,   3;\n  3: 0, 2,   9;\n  4: 0, 2,  18,   4;\n  5: 0, 2,  30,  20;\n  6: 0, 2,  45,  60,   5;\n  7: 0, 2,  63, 140,  35;\n  8: 0, 2,  84, 280, 140,  6;\n  9: 0, 2, 108, 504, 420, 54;\n","recurrence_sentence":"The row polynomials satisfy -(20*n-20-(n^3+4*n^2+n-6)*x)*P(n,x) = -(20*n-60-(n^3+2*n^2-43*n-40)*x-(n^3+8*n^2+19*n+12)*x^2)*P(n-1,x) - (40*x-(2*n^2+14*n+64)*x^2+(2*n^2+14*n+24)*x^3)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 2*x, P(1,x) = 2*x.","mathematica":"P[0, x_] := 2*x;\nP[1, x_] := 2*x;\nP[n_, x_] := P[n, x] = Expand[Together[(-(20*n - 60 - (n^3 + 2*n^2 - 43*n - 40)*x - (n^3 + 8*n^2 + 19*n + 12)*x^2)*P[n - 1, x] - (40*x - (2*n^2 + 14*n + 64)*x^2 + (2*n^2 + 14*n + 24)*x^3)*D[P[n - 1, x], x])/(-20*n + 20 + (n^3 + 4*n^2 + n - 6)*x)]];\nTable[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten","pari":"P(N) = {my(v = vector(N + 1)); v[1] = 2*x; v[2] = 2*x; for(n = 2, N, my(i = n + 1); v[i] = (-(20*n - 60 - (n^3 + 2*n^2 - 43*n - 40)*x - (n^3 + 8*n^2 + 19*n + 12)*x^2)*v[i - 1] - (40*x - (2*n^2 + 14*n + 64)*x^2 + (2*n^2 + 14*n + 24)*x^3)*deriv(v[i - 1], x))/(-20*n + 20 + (n^3 + 4*n^2 + n - 6)*x)); 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-7717563017cb9e5f","steps":["Veronese 2","\u03b8+1"],"edges":["e-7643b829dc52d64b","e-3798a6c1c99c0c64"],"text":"A159854 \u2192 Veronese 2 \u2192 \u03b8+1"},"headline":"A159854 \u2192 Veronese 2 \u2192 \u03b8+1","chain":null}