{"id":"n-bc47a5f111fa8635","revision":0,"first_index":0,"fingerprint":"f6-1e1f504198d7902a","name":"theta_plus_one of Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 3*x + 4.","polytool_family":null,"interpretation":null,"rows_observed":15,"degree_pattern":"affine","degree_slope":1,"degree_intercept":0,"palindromic":0,"gamma_positive":0,"nonnegative":1,"rr_by_factors":false,"rows":[["1"],["4","8"],["16","112","48"],["64","1104","1656","256"],["256","9392","33120","18784","1280"],["1024","73936","514344","685792","184840","6144"],["4096","556464","6917904","17830592","11529840","1669392","28672"],["16384","4075472","85038264","379379648","474224560","170076528","14264152","131072"],["65536","29347504","984873216","7086238112","15175185920","10629357168","2298037504","117390016","589824"],["262144","209102544","10949263560","121010709792","411101129880","493321355856","211768742136","29198036160","940961448","2621440"],["1048576","1479970736","118274942448","1938114679296","9905412597360","18746211522528","13867577636304","3876229358592","354824827344","7399853680","11534336"],["4194304","10431098320","1251568063704","29611088682240","219052685285760","617680911498336","720627730081392","350484296457216","66624949535040","4171893545680","57371040760","50331648"],["16777216","73328066736","13047666651360","436675632835552","4541231068450560","18307517877041184","31707620123581248","24410023836054912","8174215923211008","1091689082088880","47841444388320","439968400416","218103808"],["67108864","514638644432","134546374217448","6268277448390496","89580877867586600","500428203563721312","1231536914132488656","1407470759008558464","750642305345581968","179161755735173200","17237762983073864","538185496869792","3345151188808","939524096"],["268435456","3608241873328","1376342060840400","88125227957137216","1699695837437981680","12840544524384926448","43441133427329646624","70373537950427923200","55852885835138117088","21400907540641544080","3739330842363559696","264375683871411648","5964148930308400","25257693113296","4026531840"]],"degrees":[0,1,2,3,4,5,6,7,8,9,10,11,12,13,14],"row_sums":["1","12","176","3080","62832","1466080","38536960","1127206080","36321084800","1278502184960","48815537971200","2009572979814400","88730376185651200","4183003448752128000","209707906230773350400"],"nonn":true,"definitions":[{"position":0,"source":"derived:theta_plus_one","source_kind":"derived","equality_edge_id":null,"recurrence":{"first_index":0,"initial_polynomials":[["1"],["4","8"]],"recurrence":{"denominator":{"coeffs":[["1"],["3"]]},"terms":[{"coeff":{"coeffs":[["-16","16","8"],["-12","-12","18"],["0","-18","-27"],["0","0","-27"]]},"deriv_order":0,"offset":2,"sign":"none"},{"coeff":{"coeffs":[["0","-12","0","12"],["0","-9","-36","45"],["0","0","-27","27"]]},"deriv_order":1,"offset":2,"sign":"none"},{"coeff":{"coeffs":[["8","2"],["15","12"],["0","18"]]},"deriv_order":0,"offset":1,"sign":"none"},{"coeff":{"coeffs":[["0","3","-3"],["0","9","-9"]]},"deriv_order":1,"offset":1,"sign":"none"}]},"schema":"polytool.recurrence.v1"}}],"properties":[{"id":189877,"position":0,"claim":"real_rooted","from_index":0,"region_key":"(-inf, 0]","provenance":"edges","claim_data":{"claim":"real_rooted","from_index":0,"region":{"upper":{"closed":true,"value":"0"}}},"label":"Real-rooted","description":"Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]","region_exact":null,"edges":["e-a94914357edceb4c"]},{"id":189878,"position":1,"claim":"one_signed_coefficients","from_index":0,"region_key":null,"provenance":"derived_from_edges","claim_data":{"alternating":false,"claim":"one_signed_coefficients","from_index":0},"label":"Coefficients of one sign","description":"Every nonzero row, n >= 0: the coefficients of P_n have one sign","region_exact":null,"edges":["e-a94914357edceb4c"]},{"id":189879,"position":2,"claim":"hadamard_kernel","from_index":0,"region_key":null,"provenance":"derived_from_edges","claim_data":{"claim":"hadamard_kernel","from_index":0},"label":"Hadamard kernel (Malo)","description":"Rows P_n, n >= 0, are Hadamard kernels (preserve real-rootedness)","region_exact":null,"edges":["e-a94914357edceb4c"]},{"id":189880,"position":3,"claim":"interlacing","from_index":1,"region_key":null,"provenance":"edges","claim_data":{"claim":"interlacing","from_index":1,"kind":"weak","orientation":"unordered"},"label":"Interlacing of consecutive rows","description":"Rows P_(m-1), P_m interlace (weak, unordered) for every m >= 1","region_exact":null,"edges":["e-a94914357edceb4c"]}],"region_exact":{},"incoming_edges":[{"id":"e-a94914357edceb4c","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-bc47a5f111fa8635","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":"e994b157f5557342a3f3e48afe6e8eca1d8278f302e8bdc797b856144a42d3de","verification_polytool":"replayed","verification_lean":"not_attempted","claims":[{"claim":"real_rooted","from_index":0,"region":{"upper":{"closed":true,"value":"0"}}},{"claim":"interlacing","from_index":1,"kind":"weak","orientation":"unordered"}],"premises":[{"position":0,"node_id":"n-e224ad3e3147ef52","role":"sequence","name":"Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 3*x + 4.","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:      4,         8;\n  2:     16,       112,          48;\n  3:     64,      1104,        1656,          256;\n  4:    256,      9392,       33120,        18784,         1280;\n  5:   1024,     73936,      514344,       685792,       184840,         6144;\n  6:   4096,    556464,     6917904,     17830592,     11529840,      1669392,        28672;\n  7:  16384,   4075472,    85038264,    379379648,    474224560,    170076528,     14264152,      131072;\n  8:  65536,  29347504,   984873216,   7086238112,  15175185920,  10629357168,   2298037504,   117390016,    589824;\n  9: 262144, 209102544, 10949263560, 121010709792, 411101129880, 493321355856, 211768742136, 29198036160, 940961448, 2621440;\n","recurrence_sentence":"The row polynomials satisfy (3*n+1)*P(n,x) = -(12*n+16+(18*n^2+12*n-16)*x+(27*n^3+27*n^2-18*n-8)*x^2)*P(n-2,x) - ((9*n+12)*x+(27*n^2+36*n)*x^2-(27*n^2+45*n+12)*x^3)*d/dx P(n-2,x) + (15*n+8+(18*n^2+12*n+2)*x)*P(n-1,x) + ((9*n+3)*x-(9*n+3)*x^2)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 4 + 8*x.","mathematica":"P[0, x_] := 1;\nP[1, x_] := 4 + 8*x;\nP[n_, x_] := P[n, x] = Expand[Together[(-(12*n + 16 + (18*n^2 + 12*n - 16)*x + (27*n^3 + 27*n^2 - 18*n - 8)*x^2)*P[n - 2, x] - ((9*n + 12)*x + (27*n^2 + 36*n)*x^2 - (27*n^2 + 45*n + 12)*x^3)*D[P[n - 2, x], x] + (15*n + 8 + (18*n^2 + 12*n + 2)*x)*P[n - 1, x] + ((9*n + 3)*x - (9*n + 3)*x^2)*D[P[n - 1, x], x])/(3*n + 1)]];\nTable[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten","pari":"P(N) = {my(v = vector(N + 1)); v[1] = 1; v[2] = 4 + 8*x; for(n = 2, N, my(i = n + 1); v[i] = (-(12*n + 16 + (18*n^2 + 12*n - 16)*x + (27*n^3 + 27*n^2 - 18*n - 8)*x^2)*v[i - 2] - ((9*n + 12)*x + (27*n^2 + 36*n)*x^2 - (27*n^2 + 45*n + 12)*x^3)*deriv(v[i - 2], x) + (15*n + 8 + (18*n^2 + 12*n + 2)*x)*v[i - 1] + ((9*n + 3)*x - (9*n + 3)*x^2)*deriv(v[i - 1], x))/(3*n + 1)); 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-e224ad3e3147ef52","steps":["\u03b8+1"],"edges":["e-a94914357edceb4c"],"text":"A257622 \u2192 \u03b8+1"},"headline":"A257622 \u2192 \u03b8+1","chain":null}
