{"id":"n-6b0c5933048b26bb","revision":0,"first_index":1,"fingerprint":"f6-c7092850c22e3de4","name":"theta_plus_one of shift_x_plus_one of 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.","polytool_family":null,"interpretation":null,"rows_observed":15,"degree_pattern":"affine","degree_slope":1,"degree_intercept":-1,"palindromic":0,"gamma_positive":0,"nonnegative":1,"rr_by_factors":false,"rows":[["1"],["5","8"],["21","60","30"],["84","336","315","80"],["330","1680","2268","1120","175"],["1287","7920","13860","10080","3150","336"],["5005","36036","77220","73920","34650","7560","588"],["19448","160160","405405","480480","300300","99792","16170","960"],["75582","700128","2042040","2882880","2252250","1009008","252252","31680","1485"],["293930","3023280","9976824","16336320","15315300","8648640","2942940","576576","57915","2200"],["1144066","12932920","47616660","88682880","96996900","66162096","28588560","7687680","1216215","100100","3146"],["4457400","54915168","223092870","465585120","581981400","465585120","244432188","84015360","18378360","2402400","165165","4368"],["17383860","231784800","1029659400","2379657280","3346393050","3072861792","1901139240","798145920","224478540","40840800","4492488","262080","5915"],["67863915","973496160","4693642200","11898286400","18591072500","19275223968","13742520792","6828581760","2357024670","554268000","85357272","8019648","402220","7840"],["265182525","4071834900","21173541480","58409769600","100391791500","116008292400","93699005400","53848244736","22086194130","6401795400","1280359080","169303680","13755924","599760","10200"]],"degrees":[0,1,2,3,4,5,6,7,8,9,10,11,12,13,14],"row_sums":["1","13","111","815","5573","36633","234979","1482715","9247305","57173925","351131223","2145014919","13047105165","79075767345","477819680715"],"nonn":true,"definitions":[{"position":0,"source":"derived:theta_plus_one","source_kind":"derived","equality_edge_id":null,"recurrence":{"first_index":1,"initial_polynomials":[["1"]],"recurrence":{"denominator":{"coeffs":[["-2","4"],["-3","-4"],["3","-3"],["2","2"],["0","1"]]},"terms":[{"coeff":{"coeffs":[["0","4","-2"],["2","6","9"],["8","4","0"],["8","18","8"],["0","4","3"]]},"deriv_order":0,"offset":1,"sign":"none"},{"coeff":{"coeffs":[["0","-1","-2","-1"],["0","-4","-4","0"],["0","-4","-10","-6"],["0","0","-2","-2"]]},"deriv_order":1,"offset":1,"sign":"none"}]},"schema":"polytool.recurrence.v1"}}],"properties":[{"id":180506,"position":0,"claim":"real_rooted","from_index":1,"region_key":"(-inf, 0]","provenance":"edges","claim_data":{"claim":"real_rooted","from_index":1,"region":{"upper":{"closed":true,"value":"0"}}},"label":"Real-rooted","description":"Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]","region_exact":null,"edges":["e-7fe116191fd89191"]},{"id":180507,"position":1,"claim":"one_signed_coefficients","from_index":1,"region_key":null,"provenance":"derived_from_edges","claim_data":{"alternating":false,"claim":"one_signed_coefficients","from_index":1},"label":"Coefficients of one sign","description":"Every nonzero row, n >= 1: the coefficients of P_n have one sign","region_exact":null,"edges":["e-7fe116191fd89191"]},{"id":180508,"position":2,"claim":"hadamard_kernel","from_index":1,"region_key":null,"provenance":"derived_from_edges","claim_data":{"claim":"hadamard_kernel","from_index":1},"label":"Hadamard kernel (Malo)","description":"Rows P_n, n >= 1, are Hadamard kernels (preserve real-rootedness)","region_exact":null,"edges":["e-7fe116191fd89191"]}],"region_exact":{},"incoming_edges":[{"id":"e-7fe116191fd89191","operation":{"index_shift":0,"operation":"preserver_image","operator":"{\"shape\":\"euler_polynomial\",\"coefficients\":[{\"numerator\":[\"1\"],\"denominator\":[\"1\"]},{\"numerator\":[\"1\"],\"denominator\":[\"1\"]}]}"},"operation_detail":"euler_polynomial, shift 0","conclusion_id":"n-6b0c5933048b26bb","premise_count":1,"theorem":"Laguerre's theorem on multiplier sequences: if f is a real polynomial whose roots are all real and <= 0, then (f(k))_(k >= 0) is a multiplier sequence, so x^k -> f(k) x^k maps every real-rooted polynomial to a real-rooted polynomial or zero (Laguerre; see T. 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":"10871d71fe3f566bef2a00b0cb75a69235d55862779b624c4b634c536259fa6f","verification_polytool":"replayed","verification_lean":"not_attempted","claims":[{"claim":"real_rooted","from_index":1,"region":{"upper":{"closed":true,"value":"0"}}}],"premises":[{"position":0,"node_id":"n-141ab74a8d7e58b7","role":"sequence","name":"shift_x_plus_one of 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:      5,       8;\n   3:     21,      60,      30;\n   4:     84,     336,     315,       80;\n   5:    330,    1680,    2268,     1120,      175;\n   6:   1287,    7920,   13860,    10080,     3150,     336;\n   7:   5005,   36036,   77220,    73920,    34650,    7560,     588;\n   8:  19448,  160160,  405405,   480480,   300300,   99792,   16170,    960;\n   9:  75582,  700128, 2042040,  2882880,  2252250, 1009008,  252252,  31680,  1485;\n  10: 293930, 3023280, 9976824, 16336320, 15315300, 8648640, 2942940, 576576, 57915, 2200;\n","recurrence_sentence":"The row polynomials satisfy (2*n^3+3*n^2-3*n-2+(n^4+2*n^3-3*n^2-4*n+4)*x)*P(n,x) = (8*n^3+8*n^2+2*n+(4*n^4+18*n^3+4*n^2+6*n+4)*x+(3*n^4+8*n^3+9*n-2)*x^2)*P(n-1,x) - ((4*n^2+4*n+1)*x+(2*n^3+10*n^2+4*n+2)*x^2+(2*n^3+6*n^2+1)*x^3)*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[((8*n^3 + 8*n^2 + 2*n + (4*n^4 + 18*n^3 + 4*n^2 + 6*n + 4)*x + (3*n^4 + 8*n^3 + 9*n - 2)*x^2)*P[n - 1, x] - ((4*n^2 + 4*n + 1)*x + (2*n^3 + 10*n^2 + 4*n + 2)*x^2 + (2*n^3 + 6*n^2 + 1)*x^3)*D[P[n - 1, x], x])/(2*n^3 + 3*n^2 - 3*n - 2 + (n^4 + 2*n^3 - 3*n^2 - 4*n + 4)*x)]];\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] = ((8*n^3 + 8*n^2 + 2*n + (4*n^4 + 18*n^3 + 4*n^2 + 6*n + 4)*x + (3*n^4 + 8*n^3 + 9*n - 2)*x^2)*v[i - 1] - ((4*n^2 + 4*n + 1)*x + (2*n^3 + 10*n^2 + 4*n + 2)*x^2 + (2*n^3 + 6*n^2 + 1)*x^3)*deriv(v[i - 1], x))/(2*n^3 + 3*n^2 - 3*n - 2 + (n^4 + 2*n^3 - 3*n^2 - 4*n + 4)*x)); 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":["x \u21a6 x+1","\u03b8+1"],"edges":["e-1067be4ea4032d33","e-7fe116191fd89191"],"text":"A062145 \u2192 x \u21a6 x+1 \u2192 \u03b8+1"},"headline":"A062145 \u2192 x \u21a6 x+1 \u2192 \u03b8+1","chain":null}
