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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":"56129eb58d6c0f61de253ab38483a1651a23491317a68e03de0b37496e837985","verification_polytool":"replayed","verification_lean":"not_attempted","claims":[{"claim":"real_rooted","from_index":1,"region":{"upper":{"closed":true,"value":"0"}}},{"claim":"interlacing","from_index":2,"kind":"weak","orientation":"unordered"}],"premises":[{"position":0,"node_id":"n-a2304b34e998691c","role":"sequence","name":"Triangle read by rows: T(n, k) = [z^k] P(n, z) where P(n, z) = Sum_{k=0..n} binomial(n, k) * Pochhammer(n - k + c, k) * z^k / k! and c = 4.","uses":{"claim":"real_rooted","from_index":1,"region":{"upper":{"closed":true,"value":"0"}}},"uses_text":"Every row P_n, n >= 1, 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":1,"oeis_offset":1,"reversed":false,"trim_zeros":"none","regular_triangle":false,"rows_shown":10,"polytool_commit":"c48629374597092cc41ef4d6273f37991516f984","triangle_example":"Triangle begins:\n   1: 1;\n   2: 1,  16;\n   3: 1,  40,    90;\n   4: 1,  72,   405,    320;\n   5: 1, 112,  1134,   2240,     875;\n   6: 1, 160,  2520,   8960,    8750,    2016;\n   7: 1, 216,  4860,  26880,   47250,   27216,    4116;\n   8: 1, 280,  8505,  67200,  183750,  190512,   72030,    7680;\n   9: 1, 352, 13860, 147840,  577500,  931392,  633864,  168960,  13365;\n  10: 1, 432, 21384, 295680, 1559250, 3592512, 3803184, 1824768, 360855, 22000;\n","recurrence_sentence":"The row polynomials satisfy (n^2+n-2-(4*n^4+6*n^3-15*n^2-13*n+18)*x+(n^6+3*n^5-3*n^4-11*n^3+6*n^2+12*n-8)*x^2)*P(n,x) = (n^2+n-2-(4*n^4+6*n^3-27*n^2-17*n+10)*x+(n^6+3*n^5-24*n^4-55*n^3+22*n^2-39*n+14)*x^2+(3*n^6+15*n^5+14*n^4+3*n^3+36*n^2-23*n+6)*x^3)*P(n-1,x) + ((2*n+1)*x-(8*n^3+20*n^2-4*n+3)*x^2+(2*n^5+11*n^4+20*n^3+15*n^2+4*n-1)*x^3-(2*n^5+11*n^4+12*n^3-5*n^2+10*n-3)*x^4)*d/dx P(n-1,x) for n >= 2, with P(1,x) = 1.","mathematica":"P[1, x_] := 1;\nP[n_, x_] := P[n, x] = Expand[Together[((n^2 + n - 2 - (4*n^4 + 6*n^3 - 27*n^2 - 17*n + 10)*x + (n^6 + 3*n^5 - 24*n^4 - 55*n^3 + 22*n^2 - 39*n + 14)*x^2 + (3*n^6 + 15*n^5 + 14*n^4 + 3*n^3 + 36*n^2 - 23*n + 6)*x^3)*P[n - 1, x] + ((2*n + 1)*x - (8*n^3 + 20*n^2 - 4*n + 3)*x^2 + (2*n^5 + 11*n^4 + 20*n^3 + 15*n^2 + 4*n - 1)*x^3 - (2*n^5 + 11*n^4 + 12*n^3 - 5*n^2 + 10*n - 3)*x^4)*D[P[n - 1, x], x])/(n^2 + n - 2 - (4*n^4 + 6*n^3 - 15*n^2 - 13*n + 18)*x + (n^6 + 3*n^5 - 3*n^4 - 11*n^3 + 6*n^2 + 12*n - 8)*x^2)]];\nTable[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten","pari":"P(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = ((n^2 + n - 2 - (4*n^4 + 6*n^3 - 27*n^2 - 17*n + 10)*x + (n^6 + 3*n^5 - 24*n^4 - 55*n^3 + 22*n^2 - 39*n + 14)*x^2 + (3*n^6 + 15*n^5 + 14*n^4 + 3*n^3 + 36*n^2 - 23*n + 6)*x^3)*v[i - 1] + ((2*n + 1)*x - (8*n^3 + 20*n^2 - 4*n + 3)*x^2 + (2*n^5 + 11*n^4 + 20*n^3 + 15*n^2 + 4*n - 1)*x^3 - (2*n^5 + 11*n^4 + 12*n^3 - 5*n^2 + 10*n - 3)*x^4)*deriv(v[i - 1], x))/(n^2 + n - 2 - (4*n^4 + 6*n^3 - 15*n^2 - 13*n + 18)*x + (n^6 + 3*n^5 - 3*n^4 - 11*n^3 + 6*n^2 + 12*n - 8)*x^2)); 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}}],"derivation":{"root":"n-a2304b34e998691c","steps":["(\u03b8+1)\u00b2"],"edges":["e-42aebc790a856cde"],"text":"A062145 \u2192 (\u03b8+1)\u00b2"},"headline":"A062145 \u2192 (\u03b8+1)\u00b2","chain":null}
