Double πVerified
Historical double π
0215-03-14
Gregorian ∩ Julian
- Gregorian3/14/15
- Julian3/14/15
The next perfect pi-day
counting…
gregorian · gregorian/yy-m-dd reads3141592653589π to 13 digits
to 09:26:53 your local time
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- gregoriangregorian/yy-m-dd3141592653589π·13
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- japanesejapanese/mm-dd-yy3141592653589π·13
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Lifetime timeline
Every perfect pi-day from 2000 to 2226.
20002226
Collision search
Known witnesses, now with the CRT mechanics that determine how many collision classes survive.
Double πVerified
Deep-future double π
2197415-03-14
Gregorian ∩ Tabular Hijri
- Gregorian3/14/15
- Tabular Hijri3/14/15
Witnesses / cycleN = 12
Mean interval3.54 million years
Supercycle15,531,572,070 days
gcd filtersGregorian / Tabular Hijri = 1
Triple πModel-dependent
Triple π witness
195360930015-03-14
Gregorian ∩ Tabular Hijri ∩ Persian 33-year model
- Gregorian3/14/15
- Tabular Hijri14 Rabi' al-awwal · year …15
- Persian 33-year model14 Khordad · year …15
Witnesses / cycleN = 36
Mean interval142.37 billion years
Supercycle1,872,020,381,597,100 days
gcd filtersGregorian / Tabular Hijri = 1 · Gregorian / Persian 33-year model = 1 · Tabular Hijri / Persian 33-year model = 10
Model: Tabular Hijri + cyclic 33-year Persian arithmetic model
The gcd=10 compatibility filter is structural for these periods; N=36 and the exact witness are convention-dependent.
None yet inside the 2000–2226 window — the clean collisions are ancient or deep-future.