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  "body": "\n## Summary\n\nThe Mittag-Leffler star of a power series is the set of points that can be reached from its centre by [[analytic continuation|0M3YQJ81NB]] along straight segments.\nIt is an open set that is star-shaped with respect to the centre, and it contains the disc of convergence.\nMittag-Leffler showed that the function is given on its whole star by a series of polynomials.\nThe star is a natural domain for representing a function by summation methods beyond the disc of convergence.\n\n## Explanations\n\n### L1 human\n\nStart at the centre of a power series and walk outwards along a ray.\nContinue the function along the ray as long as possible, and stop at the first singular point.\nThe points reached on all rays form the star.\nFor $1/(1 - z)$ with centre $0$, every ray except the positive real axis can be followed forever, and the positive real axis is blocked at $1$.\nSo the star is the plane with the half-line $[1, \\infty)$ removed.\n",
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