These are lists of dates I have found which have numerical patterns in them. They are probably of no practical use at all but might be of occasional amusement as in "any excuse for a party" or "did you know your birthday this year has ...".
I got the idea when one of my friends joked in 2002 that a particular dance we were going to one evening was going encompass the time 8.02 pm on the 20th of February and therefore we could celebrate 20-02 2002 20:02!.
I wondered what other such dates could be found but not being so keen as to bother sifting through forthcoming dates myself I wrote a computer program to do it for me. It is not as versatile at recognising patterns as a human would be, of course, but it checks some basic pattern types with a thoroughness that would be too mind-numbing & time-consuming for a human to do. It certainly finds a lot of patterns in the dates!
Choose the year: 1900, 1901, 1902, 1903, 1904, 1905, 1906, 1907, 1908, 1909, 1910, 1911, 1912, 1913, 1914, 1915, 1916, 1917, 1918, 1919, 1920, 1921, 1922, 1923, 1924, 1925, 1926, 1927, 1928, 1929, 1930, 1931, 1932, 1933, 1934, 1935, 1936, 1937, 1938, 1939, 1940, 1941, 1942, 1943, 1944, 1945, 1946, 1947, 1948, 1949, 1950, 1951, 1952, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999.
Choose the year: 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026, 2027, 2028, 2029, 2030, 2031, 2032, 2033, 2034, 2035, 2036, 2037, 2038, 2039, 2040, 2041, 2042, 2043, 2044, 2045, 2046, 2047, 2048, 2049, 2050, 2051, 2052, 2053, 2054, 2055, 2056, 2057, 2058, 2059, 2060, 2061, 2062, 2063, 2064, 2065, 2066, 2067, 2068, 2069, 2070, 2071, 2072, 2073, 2074, 2075, 2076, 2077, 2078, 2079, 2080, 2081, 2082, 2083, 2084, 2085, 2086, 2087, 2088, 2089, 2090, 2091, 2092, 2093, 2094, 2095, 2096, 2097, 2098, 2099.
For other years in this & the previous millennium, the patterned dates from year 1000 to year 2999 are available as a compressed archive (7z format as it compresses this 4 times better than PK Zip or GZip). Size 429 KiB.
For even more years, download my program for finding patterned dates (10 KiB). It is written in Perl and requires a Perl interpreter to run in. A Perl interpreter comes as standard on Linux & Mac OS X and is available for Microsoft Windows. See my article anent installing Perl scripts if you need more information. Run it in a console window and give one command line parameter (the year) to test dates in a single year or two command line parameters (the start & end years) to test the dates in a range of years.
Note that the number of patterns found varies tremendously with the degree of patterning in the year itself. E.g. it found nearly nine times as many in 2000 as it did in 1999 and thirty times as many as in 1974.
It tests all combinations thereof (which can be up to 36 different representations of a single date!).
It does not take into account the separating characters (so it would spot that '2002-20-02' is a palindrome and a repeat despite the extra '-' in the second half).
It does not bother testing times of day as there so many times in each day that one can find early always easily contrive a time to match the date pattern.
(Personally, although I am from the UK, I prefer the ISO date order to the UK one because: it is logically consistent with most the way our 'Arabic' numbers & decimal quantities are written (highest place value on the left); it is consistent with how most non-decimal quantities are written (biggest units on the left as in hours-minutes-seconds & pounds-shillings-pence); it sorts alphanumerically into the chronological order; and it is a clearly defined international standard. However, even the UK date order is more logical than the muddled USA one.)
It also tests if there any patterns common to equal length substrings of digits in the number. E.g. '1969-19-11' is not a palindrome itself but in USA format with a two-digit year ('11-19-69') it can be split into two substrings ('111' & '969') both of which are palindromes.
Some inevitable duplicates are removed to save clutter in the list, e.g. arithmetic series of increment zero & geometric series of ratio 1 as they also have cyclic permutations symmetry and will so will already have been found.