{
  "ODE": "yprime=-2y,y(0)=1",
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  "unstable_T6_h_three_halves": {
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    ],
    "Euler_endpoint": "16",
    "analytic_exp_minus12": 6.14421235332821e-06,
    "amplification_per_step": "-2"
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  "constant_rhs_check": {
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  "time_rhs_old_time_check": {
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    "Euler_endpoint": "3/8",
    "analytic_half": "1/2",
    "wrong_right_time_endpoint": "5/8"
  },
  "invalid_cases_rejected": [
    "zero_steps",
    "bool_steps",
    "reverse_span",
    "nonfinite",
    "step_budget",
    "unknown_rhs"
  ],
  "scope": "known authored IVP and fixed steps, no convergence flag from budget completion; exact arithmetic steps versus floating exponential reference, no solve_ivp/forecast/NeuralODE/model/Opera claim"
}