{"id":"e-296c9d0ea53bd991","operation":{"index_shift":0,"operation":"preserver_image","operator":"{\"shape\":\"derivative_polynomial\",\"coefficients\":[{\"numerator\":[\"1\"],\"denominator\":[\"1\"]},{\"numerator\":[\"1\"],\"denominator\":[\"1\"]}]}"},"operation_detail":"derivative_polynomial, shift 0","conclusion_id":"n-0722f6e57948ddf4","premise_count":1,"theorem":"Laguerre's theorem on differential operators: if phi is a real polynomial with only real roots, then phi(D) maps every real-rooted polynomial to a real-rooted polynomial or zero (write phi(D) = C D^j prod (1 + c_i D); D preserves real-rootedness by Rolle's theorem and p + c p' is real-rooted for every real c by Rolle's theorem applied to e^(x/c) p; Polya--Schur 1914); when the coefficients of phi have one sign, coefficients of one sign stay of one sign; applied to phi(n, .) for each n","lean_route":null,"lean_declarations":["RealRooted.splits_add_C_mul_derivative_all","RealRooted.splits_C_mul_add_derivative","Polynomial.Splits.derivative"],"certificate_hash":"a9f96ad96ed2c9361659e95c39b1ff4ace91bed5e08974f3b8f5ebb16c02162f","verification_polytool":"replayed","verification_lean":"not_attempted","certificate_kind":"preserver_image","certificate_raw_size":23616,"certificate_compressed_size":3819,"conclusion_name":"one_plus_derivative of Riordan array ((1-x)/(1+x), x/(1+x)^2).","claims":[{"claim":"real_rooted","from_index":1,"region":{}},{"claim":"interlacing","from_index":3,"kind":"weak","orientation":"unordered"}],"premises":[{"position":0,"node_id":"n-afb1686ffa6592c0","role":"sequence","name":"Riordan array ((1-x)/(1+x), x/(1+x)^2).","uses":{"claim":"real_rooted","from_index":1,"region":{}},"uses_text":"Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, +inf)"}],"cited_by":[{"node_id":"n-0722f6e57948ddf4","claim":"real_rooted"},{"node_id":"n-0722f6e57948ddf4","claim":"interlacing"}]}