{"id":"n-92154eddb2a3f6aa","revision":0,"first_index":1,"fingerprint":"f6-1cb864a0be18acfd","name":"theta_plus_one of Triangle T(n, k) = coefficients of ( t(n, x) ) where t(n, x) = (1-x)^(n+1)*p(n, x)/x, p(n, x) = x*D( p(n-1, x) ), with p(1, x) = x/(1-x)^2, p(2, x) = x*(1+x)/(1-x)^3, and p(3, x) = x*(1+12*x+x^2)/(1-x)^4, read by rows.","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","24","3"],["1","54","81","4"],["1","116","486","232","5"],["1","242","2154","2872","605","6"],["1","496","8277","22976","13795","1488","7"],["1","1006","29295","147084","183855","58590","3521","8"],["1","2028","98448","822696","1838550","1234044","229712","8112","9"],["1","4074","319680","4209632","15362970","18435564","7366856","852480","18333","10"],["1","8168","1014039","20248448","113649130","221226768","159108782","40496896","3042117","40840","11"],["1","16358","3164637","93162260","770730130","2282013300","2662348850","1233168208","209615085","10548790","89969","12"],["1","32740","9763818","414844200","4901726075","21091089048","37272883900","28121452064","8823106935","1037110500","35800666","196440","13"],["1","65506","29880774","1802579464","29694182875","179485175898","457760351748","523154687712","269227763847","59388365750","4957093526","119523096","425789","14"],["1","131040","90919689","7688410240","173256382005","1433241249888","5088916809165","8370475003392","6542893040355","2388735416480","381164040411","23065230720","393985319","917280","15"],["1","262110","275510907","32329582236","981608063625","10886431741794","52343565579515","119306944349976","134220312393723","74776522256450","19958458193289","2355859352700","105071142267","1285717566","1965825","16"],["1","524252","832430196","134461199208","5433396029460","79453746566964","506114166409628","1552667732851408","2415965623087014","1940834666064260","795322261500844","158907493133928","14126829676596","470614197228","4162150980","4194016","17"]],"degrees":[2,3,4,5,6,7,8,9,10,11,12,13,14,15,16],"row_sums":["28","140","840","5880","47040","423360","4233600","46569600","558835200","7264857600","101708006400","1525620096000","24409921536000","414968666112000","7469435990016000"],"nonn":true,"definitions":[{"position":0,"source":"derived:theta_plus_one","source_kind":"derived","equality_edge_id":null,"recurrence":{"first_index":1,"initial_polynomials":[["1","24","3"],["1","54","81","4"]],"recurrence":{"terms":[{"coeff":{"coeffs":[["0","0","0"],["0","0","-2"],["0","0","-1"]]},"deriv_order":0,"offset":2,"sign":"none"},{"coeff":{"coeffs":[["0","0","-2","2"],["0","0","-1","1"]]},"deriv_order":1,"offset":2,"sign":"none"},{"coeff":{"coeffs":[["1","2"],["0","2"]]},"deriv_order":0,"offset":1,"sign":"none"},{"coeff":{"coeffs":[["0","1","-1"]]},"deriv_order":1,"offset":1,"sign":"none"}]},"schema":"polytool.recurrence.v1"}}],"properties":[{"id":185908,"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-140d5424e0f44f15"]},{"id":185909,"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-140d5424e0f44f15"]},{"id":185910,"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-140d5424e0f44f15"]},{"id":185911,"position":3,"claim":"interlacing","from_index":2,"region_key":null,"provenance":"edges","claim_data":{"claim":"interlacing","from_index":2,"kind":"weak","orientation":"unordered"},"label":"Interlacing of consecutive rows","description":"Rows P_(m-1), P_m interlace (weak, unordered) for every m >= 2","region_exact":null,"edges":["e-140d5424e0f44f15"]}],"region_exact":{},"incoming_edges":[{"id":"e-140d5424e0f44f15","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-92154eddb2a3f6aa","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":"f9b57ad95cc74539b9c22fb81aacdc94e89aea0370247d04c63733c97f287269","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-52497a04d5e26922","role":"sequence","name":"Triangle T(n, k) = coefficients of ( t(n, x) ) where t(n, x) = (1-x)^(n+1)*p(n, x)/x, p(n, x) = x*D( p(n-1, x) ), with p(1, x) = x/(1-x)^2, p(2, x) = x*(1+x)/(1-x)^3, and p(3, x) = x*(1+12*x+x^2)/(1-x)^4, read by rows.","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,    24,       3;\n   2: 1,    54,      81,        4;\n   3: 1,   116,     486,      232,         5;\n   4: 1,   242,    2154,     2872,       605,          6;\n   5: 1,   496,    8277,    22976,     13795,       1488,          7;\n   6: 1,  1006,   29295,   147084,    183855,      58590,       3521,          8;\n   7: 1,  2028,   98448,   822696,   1838550,    1234044,     229712,       8112,         9;\n   8: 1,  4074,  319680,  4209632,  15362970,   18435564,    7366856,     852480,     18333,       10;\n   9: 1,  8168, 1014039, 20248448, 113649130,  221226768,  159108782,   40496896,   3042117,    40840,    11;\n  10: 1, 16358, 3164637, 93162260, 770730130, 2282013300, 2662348850, 1233168208, 209615085, 10548790, 89969, 12;\n","recurrence_sentence":"The row polynomials satisfy P(n,x) = -(n^2+2*n)*x^2*P(n-2,x) - ((n+2)*x^2-(n+2)*x^3)*d/dx P(n-2,x) + (1+(2*n+2)*x)*P(n-1,x) + (x-x^2)*d/dx P(n-1,x) for n >= 3, with P(1,x) = 1 + 24*x + 3*x^2, P(2,x) = 1 + 54*x + 81*x^2 + 4*x^3.","mathematica":"P[1, x_] := 1 + 24*x + 3*x^2;\nP[2, x_] := 1 + 54*x + 81*x^2 + 4*x^3;\nP[n_, x_] := P[n, x] = Expand[-(n^2 + 2*n)*x^2*P[n - 2, x] - ((n + 2)*x^2 - (n + 2)*x^3)*D[P[n - 2, x], x] + (1 + (2*n + 2)*x)*P[n - 1, x] + (x - x^2)*D[P[n - 1, x], x]];\nTable[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten","pari":"P(N) = {my(v = vector(N)); v[1] = 1 + 24*x + 3*x^2; v[2] = 1 + 54*x + 81*x^2 + 4*x^3; for(n = 3, N, my(i = n); v[i] = -(n^2 + 2*n)*x^2*v[i - 2] - ((n + 2)*x^2 - (n + 2)*x^3)*deriv(v[i - 2], x) + (1 + (2*n + 2)*x)*v[i - 1] + (x - 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, v[i])))};\nT(10)","reading":{"first_row":1,"offset":1,"reversed":false,"trim_zeros":"none","regular_triangle":false}}],"derivation":{"root":"n-52497a04d5e26922","steps":["\u03b8+1"],"edges":["e-140d5424e0f44f15"],"text":"A166343 \u2192 \u03b8+1"},"headline":"A166343 \u2192 \u03b8+1","chain":null}
