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A331542
The speed of light in furlongs per fortnight.
0
1, 8, 0, 2, 6, 1, 7, 4, 9, 9, 7, 8, 5, 2, 5, 4, 1, 1, 5, 9, 6, 2, 7, 7, 7, 3, 8, 0, 1, 0, 0, 2, 1, 4, 7, 4, 5, 8, 8, 4, 0, 3, 7, 2, 2, 2, 6, 1, 9, 8, 9, 9, 7, 8, 5, 2, 5, 4, 1, 1, 5, 9, 6, 2, 7, 7, 7, 3, 8, 0, 1, 0, 0, 2, 1, 4, 7, 4, 5, 8, 8, 4, 0, 3, 7, 2, 2, 2, 6, 1, 9, 8
OFFSET
13,2
COMMENTS
Arguably the most well known FFF constant. Note that its precise value depends on the definition of the furlong being used. The value given here is using the international definition of the inch which equals 25.4 millimeters, thus one furlong equals 201.168 meters precisely.
From Jianing Song, Jan 25 2020: (Start)
Decimal expansion of 2518256647200000/1397.
Period 42: repeat [9, 9, 7, 8, 5, 2, 5, 4, 1, 1, 5, 9, 6, 2, 7, 7, 7, 3, 8, 0, 1, 0, 0, 2, 1, 4, 7, 4, 5, 8, 8, 4, 0, 3, 7, 2, 2, 2, 6, 1, 9, 8] since a(21). (End)
FORMULA
1802617499785.2541159627773801002... furlongs/fortnight = (speed of light in meters/second) * (meter-to-furlong conversion) * (seconds/fortnight) = (299792458 meters/second) * (1/201.168 furlongs/meter) * (1209600 seconds/fortnight).
a(n) = 9 - a(n-21) for n >= 42. - Jianing Song, Jan 25 2020
CROSSREFS
Sequence in context: A265294 A062522 A117888 * A295330 A094240 A200093
KEYWORD
nonn,cons,less,dumb
AUTHOR
Scott R. Shannon, Jan 19 2020
EXTENSIONS
More terms from Jianing Song, Jan 25 2020
STATUS
approved