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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":"e0606ad5c9c2dd7abdc08dc7833cb1883168585df32fd71142205b2d12d8e656","verification_polytool":"replayed","verification_lean":"not_attempted","claims":[{"claim":"real_rooted","from_index":0,"region":{"upper":{"closed":true,"value":"0"}}},{"claim":"interlacing","from_index":2,"kind":"weak","orientation":"unordered"}],"premises":[{"position":0,"node_id":"n-bf08de87964eed6e","role":"sequence","name":"basis_map_A013610 of Triangle read by rows. T(n, k) = binomial(n, k)*binomial(n - 1, n - 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:     3,     12;\n  3:    10,     72,      81;\n  4:    35,    360,     810,      432;\n  5:   126,   1680,    5670,     6480,     2025;\n  6:   462,   7560,   34020,    60480,    42525,     8748;\n  7:  1716,  33264,  187110,   453600,   510300,   244944,    35721;\n  8:  6435, 144144,  972972,  2993760,  4677750,  3674160,  1285956,  139968;\n  9: 24310, 617760, 4864860, 18162144, 36486450, 40415760, 23575860, 6298560, 531441;\n","recurrence_sentence":"The row polynomials satisfy (2*n^3-3*n^2+n+(3*n^4-6*n^3+3*n^2)*x)*P(n,x) = (8*n^3-16*n^2+10*n-2+(12*n^4+6*n^3-54*n^2+48*n-12)*x+(27*n^4-36*n^3-18*n^2+45*n-18)*x^2)*P(n-1,x) - ((4*n^2-4*n+1)*x+(6*n^3+12*n^2-18*n+6)*x^2+(18*n^3-18*n+9)*x^3)*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[Together[((8*n^3 - 16*n^2 + 10*n - 2 + (12*n^4 + 6*n^3 - 54*n^2 + 48*n - 12)*x + (27*n^4 - 36*n^3 - 18*n^2 + 45*n - 18)*x^2)*P[n - 1, x] - ((4*n^2 - 4*n + 1)*x + (6*n^3 + 12*n^2 - 18*n + 6)*x^2 + (18*n^3 - 18*n + 9)*x^3)*D[P[n - 1, x], x])/(2*n^3 - 3*n^2 + n + (3*n^4 - 6*n^3 + 3*n^2)*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] = ((8*n^3 - 16*n^2 + 10*n - 2 + (12*n^4 + 6*n^3 - 54*n^2 + 48*n - 12)*x + (27*n^4 - 36*n^3 - 18*n^2 + 45*n - 18)*x^2)*v[i - 1] - ((4*n^2 - 4*n + 1)*x + (6*n^3 + 12*n^2 - 18*n + 6)*x^2 + (18*n^3 - 18*n + 9)*x^3)*deriv(v[i - 1], x))/(2*n^3 - 3*n^2 + n + (3*n^4 - 6*n^3 + 3*n^2)*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-b1b19325e0094118","steps":["basis A013610","\u03b8+1"],"edges":["e-59715d0ff282a908","e-76fb56a6840d173b"],"text":"A367270 \u2192 basis A013610 \u2192 \u03b8+1"},"headline":"A367270 \u2192 basis A013610 \u2192 \u03b8+1","chain":null}
