We show that the tritronquée solution yt of the Painlevé equation P I that behaves algebraically for large z with arg z = π/5, is analytic in a region containing the sector z = 0, arg z ∈ − 3π 5 , π and the disk z : |z| < 37 20 . This implies the Dubrovin conjecture, an important open problem in the theory of Painlevé transcendents. The method, building on a technique developed in [4], is general and constructive. As a byproduct, we obtain the value of the tritronquée and its derivative at zero, also important in applications, within less than 1/100 rigorous error bounds. arXiv:1209.1009v2 [math.CA] 23 Oct 2014 24 O. COSTIN 1 , M. HUANG 2 , S. TANVEER 1 8.1. Values of intermediate constants for ρ = 3. The numerical values of these constants might be helpful to the reader who would like to double-check the estimates. These are: J M = 0.282580···, jm = 0.64374···, Y 1,M = 1.16314···, Y 1,R,M = 0.132618···, E M = 0.0490292··· z 2,R,M = 0.54226···, z 2,M = 0.91863···, Mq = 0.066702···, M L,q = 0.075708···, V M = 0.2239···, T M = 0.0385··· M 1 = 1.13838···, M 2 = 0.04303···, M 3 = 0.28346···, M 4 = 0.45227···, M 5 = 0.05430···, M 6 = 0.00231···, M 7 = 0.02018··· 9. Acknowledgments