Javanese Calendar (Sultan Agung / Anno Javanico) (爪哇曆)

THE JAVANESE CIVIL CALENDAR — Sultan Agung's reform of 1633, the calendar that fused two civilizations: it kept the Hindu-Javanese SAKA year count (1555) but swapped solar months for Islamic lunar ones, and it is still printed in every Indonesian almanac. Twelve months Sura..Besar, the EIGHT-YEAR TAHUN CYCLE (Alip, Ehé, Jimawal, Jé, Dal, Bé, Wawu, Jimakir), the WINDU with its four names (Adi, Kunthara, Sengara, Sancaya — a 32-year round), and the 120-year KURUP correction. THE ARITHMETIC ASSERTED AT LOAD: a windu is 2835 days = 3⁴×5×7 = exactly 405 weeks = 81 selapan, so every date's weton repeats every eight years — and 1 Sura of every Alip year falls on SELASA PON, the kurup's own name (Asapon), proven against the weton engine for all fifteen windu; and the KURUP LAW, 15 windu − 1 day = 42,524 = exactly four tabular-Islamic 30-year cycles — the dropped day that locks Javanese and Hijri time forever. The wuntu recension dispute SETTLED by published anchors (1 Sura Jimawal 1957 = Thursday 20 July 2023 decides for the palace rule); the Friday-Kliwon 2025 anchor asserted with weekday AND pasaran. Kurup Asapon window served; Aboge communities' one-day-behind reckoning disclosed, never blended. Indonesian becomes five systems, and the catalogue's 300th. Pure compute, no LLM.

Cost: 1 TIAN Points per call. tRPC procedure javaneseCalendar.day.