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A375820
Decimal expansion of 333/106.
1
3, 1, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6, 4, 1, 5, 0, 9, 4, 3
OFFSET
1,1
COMMENTS
Approximation of Pi accurate up to five digits.
Periodic of period [4, 1, 5, 0, 9, 4, 3, 3, 9, 6, 2, 2, 6] of length 13.
REFERENCES
David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 49.
FORMULA
Equals (2*355 - 377)/(2*113 - 120), where A068079 = 355/113 and A210622 = 377/120 [Adriaen Metius]. See Wells.
EXAMPLE
3.1415094339622641509433962264150943396226415...
MATHEMATICA
RealDigits[333/106, 10, 100][[1]]
PROG
(Python)
def A375820(n): return (2, 2 , 6, 4, 1, 5, 0, 9, 4, 3, 3, 9, 6)[n%13] if n>2 else 5-(n<<1) # Chai Wah Wu, Aug 30 2024
CROSSREFS
KEYWORD
nonn,cons,easy
AUTHOR
Stefano Spezia, Aug 30 2024
STATUS
approved