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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":"c6e0773bd2c4b46d0c311c95a26f032e79d5120169a9e9a10192ce578e6c3f33","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-991b9bffcf8ddedb","role":"sequence","name":"Triangle T(n,k) (n >= 1, 0 <= k <= floor((n-1)/2)) read by rows, where T(n,k) = (k+1)T(n-1,k) + (2n-4k)T(n-1,k-1).","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: 1;\n  2: 1,    4;\n  3: 1,   16;\n  4: 1,   44,     48;\n  5: 1,  104,    408;\n  6: 1,  228,   2160,   1088;\n  7: 1,  480,   9216,  15872;\n  8: 1,  988,  34848, 137216,  39680;\n  9: 1, 2008, 122328, 920576, 884480;\n","recurrence_sentence":"The row polynomials satisfy P(n,x) = -(4*n^2-4*n-8)*x^2*P(n-2,x) - ((2*n+2)*x^2-(8*n+8)*x^3)*d/dx P(n-2,x) + (1+(4*n-4)*x)*P(n-1,x) + (x-4*x^2)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 1.","mathematica":"P[0, x_] := 1;\nP[1, x_] := 1;\nP[n_, x_] := P[n, x] = Expand[-(4*n^2 - 4*n - 8)*x^2*P[n - 2, x] - ((2*n + 2)*x^2 - (8*n + 8)*x^3)*D[P[n - 2, x], x] + (1 + (4*n - 4)*x)*P[n - 1, x] + (x - 4*x^2)*D[P[n - 1, x], x]];\nTable[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten","pari":"P(N) = {my(v = vector(N + 1)); v[1] = 1; v[2] = 1; for(n = 2, N, my(i = n + 1); v[i] = -(4*n^2 - 4*n - 8)*x^2*v[i - 2] - ((2*n + 2)*x^2 - (8*n + 8)*x^3)*deriv(v[i - 2], x) + (1 + (4*n - 4)*x)*v[i - 1] + (x - 4*x^2)*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 - 1, v[i])))};\nT(9)","reading":{"first_row":0,"offset":0,"reversed":false,"trim_zeros":"none","regular_triangle":false}}],"derivation":{"root":"n-ff270bcb802a85af","steps":["\u03b3 (shift +1)","\u03b8+1"],"edges":["e-e49ea542bfed6bbf","e-f727bc245399bdee"],"text":"A008292 \u2192 \u03b3 (shift +1) \u2192 \u03b8+1"},"headline":"A008292 \u2192 \u03b3 (shift +1) \u2192 \u03b8+1","chain":null}