This year the winter will arrive really on December 21. Usually if falls on 21 or 22. It has not fallen on 23 since 1903, and it won't happen up to 2303, 2307, 2311 and 2315. On day 20, he goes up again to 1664, 1668, 1672, 1676, 1680, 1684, 1688, 1692, 1696 and 1697, and then up to 2080, 2084, 2088, 2092, 2096, 2488, 2492 and 2496 nothing to be done.
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