Limerick (12+144+20 + 3 4**(1/2))/7 + 5*11 = 9**2 + 0 A dozen, a gross, and a score, Plus three times the square root of four, Divided by seven Plus five times eleven Is nine squared and naught a bit more. I'm trying to relate this limerick to calendrics. The first sum works out to 182, which is half a year. Dividing by seven gives number of weeks in 1/2 year. I'm not yet sure what to do about the rest. Anyway, thinking about this has got me starting to think of a calendar related item for as many integers as possible, along these lines: 2: days in a weekend 3: Maximum number of Friday the 13ths in a year. 4: quarters in a year 4: solstices and equinoxes in a year 4: number of principal phases of the moon 5: days in a work week 5: days at the end of the Egyption calendar and Mayan Haab not belonging to a month 6: Jubilees in 293 solar years 7: days in a week 8: years in an Octaeteris 8: days in Roman market day cycle 8: leap days in 33-year cycle 9: weeks equal to 2 months and 2 days for April, June, August, October and December 9: Lords of the night cycle of the Mayan calendar - combines with calendar round to make cycle of 170820 days 10: days in the Egyptian and French Republican "week" (decade) 11: years after which Easter is often the same 11: leap weeks in 62-year cycle 11: leap years in Tabular Islamic 30-year cycle 11: usual annual epact increment (mod 30) 12: months in Julian/Gregorian calendar year 12: lunar months in a Islamic year 12: animals in the Chinese zodiac 13: months in calendar year with 28 day months 13: lunar months in a lunisolar long year 13: weeks in a quarter 13: day numbers in a Tzolkin 14: days in two weeks (fortnight) 14: lunar months in a full moon cycle (approx) 14: different calendars in Julian, Gregorian, Hebrew calendars, taking account of the days of the week 14: months in maximum period that one Friday 13th comes after the previous Friday 13. 15: lunar months in a short yerm 15: years in Roman cycle of indiction (tax collection) 15: leap days in 62-year cycle 16: full moon cycles (fumocies) in a Saros (approx) 17: lunar months in a full yerm 18: fumocies in 251 lunations (very close) 18: years in a Saros 18: named Uinals in a Tun in the Mayan calendar 19: years in a Metonic cycle 19: days in a Bahai month and Bahai months in a year 20: base of Mayan counting system 20: day names in a Tzolkin 24: fumocies in 334 lunar months or 27 years 25: years of 365 days in an Egyptional lunar cycle of 309 months 26: weeks in half a year and fortnights in a whole year (approx) 27: years in 24 fumocies or 334 lunar months 28: years in a Julian cycle with days of week 28: days in month of 13 month calendar 28: days in February in a common year 29: days in February in a leap year 29: days in a short lunar month 30: days in a long lunar month 30: days in April, June, September or November 30: The number of years in a cycle of the Tabular Islamic Calendar 31: days in any other Gregorian or Julian month 32: lunar months in a week of weeks (see 135 and 945)33: years of 365 days plus 8 leap days have a mean length of 365.242424.. days 33: years of 365 days plus 8 leap days have a mean length of 365.242424.. days 35: different possible dates for Easter (from March 22 to April 25) 38: eclipse seasons in a Saros 38: weeks in approximately 9 lunar months. 39: sideral years very close to 14245 days 48: Number of Friday the 13ths in a 28-year Julian cycle 49: 364-day years in a Jubilee 49: lunar months reckoned to be 1447 days 52: weeks in a year (approx) 55: weeks in an abundant long lunisolar year 59: Usually, the number of days in two consecutive lunar calendar months 60: Base of the Babylonian counting system, which survives in our minutes and seconds. 60: Years in Chinese calendar cycle based on 5 elements and 12 zodiac animals 61: eclipse seasons in an Inex 61: weeks in maximum period that one Friday 13th comes after the previous Friday 13. 62: years with 15 leap days has a whole number of weeks and of 5-day cycles. The mean year is 365.241935... days. 64: lunar months close to 63 30-day months (see 703 for better approximation) 70: years for sidereal year to fall one day behind tropical year (approx) 71: leap weeks in 400 years for Gregorian mean year of 365.2425 days. 73: days in 1/5 year (approx) 73: days in 1/8 Venus synodic period (approx) 79: Number of years in a more accuate cycle for the Tabular Islamic calendar with 29 leap years. 87: days that eight 12-month lunar years drift against eight solar years 91: days in a quarter (approx) 97: leap days in 400-year Gregorian cycle 97: weeks in appriximately 23 lunar months 99: lunar months in an Octaetris 103: years in a lunisolar calendar have 20 more abundant than deficient on average 103: thousands of days in 282 years (approx) 103: years reckoned to be 37620 days = 6*30*11*19 days. 110: short (29-day) months in a Metonic Cycle (of 6940 days) 122: months in solar year of months 3 or 2 days long (see 241). 123: long years in 334-year cycle 125: long (30-day) months in a Metonic cycle (of 6940 days) 126: abundant less deficient years in 649-year cycle 128: years a Julian leap day is skipped would produce a mean year of 365.2421875 days 130: long years in 353-year cycle 135: lunar months in a Tritos and weeks in a week of weeks 138: weeks reckoned to equal to 965 units of 2/59 lunations. 152: Venus Synodic cycles in Venus transit cycle of 243 years 153: days in 5 consecutive Julian/Gregorian months not containing February 157: Venus Synodic Cycles in 251 tropical years (approx) 161: months repeating 1 and 2 days per month for 161 months (241 days) form an accurate solar calendar with a year boundary every 244 months. 183: 49-month cycles in 725 years 202: abundant less deficient years in 1040-year cycle 206: solar years about 209 years of 360 days 209: years of 360 days is close to 206 solar years 210: days in an Indonesian cycle of integer numbers of 5, 6, and 7-day cycles 223: lunar months in a Saros (approx) 223: lunar months in 16 fumocies (approx) 223: lunar months in 18 years (approx) 223: consecutive lunations is a very consistent period of time 6585.2653 .. 6585.3701 days 235: lunar months in a Metonic cycle 239: long years in 649-year cycle 241: days grouped alternately in months of 1 and 2 days (see 161) form an accurate solar calendar 241: days grouped in 3 day months for 160 months followed by a 2 day month form an accurate solar calendar (new year every 122 months). 243: years in Venus transit cycle (152 Venus synodic cycles) 248: thousands of days reckoned to be 679 years 251: lunar months in 18 full moon cycles (approx) 251: tropical years in 157 Venus synodic cycles (approx) 258: centuries in a cycle of the precession of equinoxes (approx) 260: days in a Mayan Tzolkin 261: weeks in five years with 2 leap days 282: years in 103,000 days (approx) 293: solar years in six jubilees 294: years of 364 days is very close to 293 solar years 299: Venus Synodic cycles in 478 sidereal years (approx) 309: lunar months in an egyptian 25-year cycle 313: weeks in six years with one leap day 334: lunar months in 27 years or 24 fumocies 334: years reckoned to be 4131 lunar months 353: years reckoned to be 4366 lunar months 353: days in a deficient short lunisolar year 354: days in a regular short lunisolar year 355: days in a abundant short lunisolar year 358: lunar months in an Inex 364: days in 52 weeks 365: days in a solar common year 365: days in a Egyptian calendar year, Mayan Haab cycle 366: days in a solar leap year 371: days in a leapweek year (53 weeks) 371: tithis in a solar year without saltus lunae (372 with saltus lunae). 372: years in a Gregoriana reckoned to be 4601 lunar months and also 784 eclipse seasons 383: long years in 1040-year cycle 383: days in a deficient long lunisolar year 384: days in a regular long lunisolar year 385: days in an abundant long lunisolar year (exactly 55 weeks) 391: years reckoned to be 403 lunar years and also 824 eclipse seasons (Grattan-Guinness cycle) 399: short (29-day) months in a yerm calendar cycle (52 yerms) 400: years in a Gregorian leap year cycle 409: lunar months in 33 years of 366 days (25 yerms) 412: days in a full moon cycle - fumocy (approx) 443: days in a short yerm 441: short (29-day) months in Callypic cycle 451: long (30-day) months in a yerm calendar cycle (52 yerms) 478: sidereal years in 299 Venus Synodic Cycles (approx) 499: long (30-day) months in Callypic cycle 502: days in a full yerm 532: years in a Julian Easter cycle 574: weeks in 11 years with 3 leap days 584: days in a synodic period of Venus (approx) 626: weeks in 12 Gregorian years with a dropped leap day 649: years in shortest accurate lunisolar cycle (8027 months, 237042 days) 654: lunar months very close to 623 31-day months 679: years reckoned to be 248,000 days 688: Friday 13ths in a 400-year Gregorian cycle 703: lunar months very close to 692 30-day months 725: years in 183 49-month cycles 793: number of 1080ths of an hour that the mean Hebrew month exceeds 29 days 12 hours. 819: One of Mayan cycles -- color and cardinal direction cycle through 4 values once every 819 days 850: lunar months in a 52-yerm cycle 887: weeks in 17 years with 4 leap days 896: years in the cycle of Bonavian Civil calendar (=7*128) 940: lunar months in a callypic cycle 945: days in a week of weeks 945: days in 32 synodic months (approx) 945: days in 31 Gregorian months (frequently) 965: number of lunations reckoned to occur in 966 months avaraging 29.5 days. 992: days that should have one lunisolar intercalary month 1004: days in 34 synodic months (approx) 1004: days in 33 Gregorian months (frequently) 1040: years in accurate lunisolar cycle (12863 months, 379852 days). 1447: days in a 49-month cycle (lunar) 1461: days in 4 Julian years including a leap year weeks in 28-year Julian Calendar Cycle 1507: days should have 1 leap day to match Vernal Equinox year length 1508: days should have 1 leap day to match mean tropical year length 1689: years in a Goddess lunar calendar cycle (649-year cycle + 1040-year cycle) 2087: weeks in 40 Gregorian years with a dropped leap day 2835: days in a Windu cycle of 96 lunar months (3*945) 2894: days (twice 1447) in 98 synodic months (approx), also 7 full moon cycles (approx) and 28 days short of 8 Julian years 2922: days in an Octaetris 3235: weeks in 62-year cycle 4131: lunar months in 334-year cycle 4366: lunar months in 353-year cycle 5009: weeks in 96 Gregorian years with a dropped leap day 6300: years before New Eastern Orthodox calendar repeats (including week) 6585: days in Saros (approx) 6686: Martian days in a Martian 10-year cycle 6939: days in a Metonic cycle (approx) 6940: days in a Metonic cycle (approx) 7200: days in Mayan Katun 7591: days in 13 Synodic Venus Cycles (approx) 7980: years in Julian day cycle (28x19x15) 8027: lunar months in 649-year cycle 9125: days in an egyptian lunar cycle of 25 years and of 309 lunar months 10227: days in 28-year Julian day of week cycle 10631: days in a Tabular Islamic 30-year cycle 12053: days in a 33-year cycle with 8 leap years 12863: lunar months in 1040-year cycle 14245: days in 39 sidereal years (approx) 14598: days in 25 Venus synodic cycles (approx) 17836: days in a Jubilee (49 364-day years) 18980: days in a Mayan calendar round 19756: days in three Saroses (accurate to 1 hour) 20871: weeks in a Gregorian 400-year cycle 22645: days in 62-year cycle 25101: days in a 52-yerm cycle 25920: months in which Hebrew molad repeats 27759: days in a Callypic 76-year cycle and weeks in a 532-year Julian Easter cycle 93600: days in Mayan short count (Tzolkin X Katun) 107,016: days in six jubilee cycle (294 364-day years) 121,991: days in 334-year cycle (approx) 144,000: days in Mayan Baktun 146,097: days in a Gregorian 400-year cycle 170,820: days in Mayan calendar round X Nine lords of the night cycle 237,042: days in 649-year cycle 379,852: days in 1040-year cycle 416,385: weeks in Julian day cycle (7980 Julian years) 1,872,000: days in one cycle of Mayan long count 2,038,400: Gregorian years in 2,038,401 years of length 1/293 Jubilee 2,880,000: days in Mayan Pictun 2,914,695: days in Julian day cycle (7980 Julian years) 5,700,000: years in Gregorian Easter Cycle 57,600,000: days in Mayan Kinchiltun 744,510,312: days before Gregorian and 28/293 calendar resync (2,038,400 Greg. years). 744,510,312: days in 6957 jubilees etc. The goal is to have something for as many numbers as possible. If you'd like to add entries yourself, feel free to upload an amended version of this file. -- Victor Engel Added 334/27/24 relationship. Victor Engel 2003-01-27 I've added a few, and made some corrections. Victor Engel 2003-01-14 I've added many. Karl Palmen 2003-01-14 I've added Venus and Sidereal year and others 2003-11-05 Additions paraphrased from Karl's email post of 2002-01-31 referencing Sepp's calendar numbers Copyright by Contributors (alphabetized by last name): Victor Engel Jean Fontaine Clarence Kelogg Karl Palmen Sepp Rothwangl Amos Shapir I've added more. Karl Palmen 2002-12-04 More Mayan calendar numbers added. Victor Engel 2003-09-28 Add number of long and short months in Callypic and Yerm Calendar Cycles Cut long lines, make some other small modifications Karl Palmen 2003-09-29. Add some week counts. Karl Palmen 2004-02-04 Add numbers related to 6957 jubilees Victor Engel 2004-02-13 Added days in a Triple Saros (19756) and lunar months in a week of weeks (32) correct typos and some other things. Karl Palmen 2004-11-15 Cleaned up format (was missing line breaks) and merge items missing from numbers09.txt