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A318523
Decimal expansion of sqrt((1/5)^(1/5)+(4/5)^(1/5)).
2
1, 2, 9, 6, 5, 8, 4, 8, 0, 7, 6, 6, 5, 0, 1, 8, 3, 0, 7, 4, 9, 2, 4, 0, 1, 6, 4, 5, 8, 2, 9, 1, 3, 5, 7, 7, 7, 4, 8, 5, 1, 3, 5, 2, 1, 3, 4, 8, 5, 3, 0, 2, 2, 6, 1, 4, 2, 7, 4, 3, 1, 4, 1, 8, 0, 8, 9, 6, 1, 9, 4, 0, 5, 0, 6, 2, 0, 3, 2, 7, 7, 8, 6, 3, 6, 1
OFFSET
1,2
COMMENTS
Ramanujan's question 1070 (i) asks for a proof of the identities
sqrt((1/5)^(1/5)+(4/5)^(1/5)) = (1+2^(1/5)+8^(1/5))^(1/5) = (16/125)^(1/5)+(8/125)^(1/5)+(2/125)^(1/5)-(1/125)^(1/5).
REFERENCES
S. Ramanujan, Coll. Papers, Chelsea, 1962, page 334, Question 1070.
EXAMPLE
1.296584807665018307492401645829135777485135213485302261427431418...
MATHEMATICA
RealDigits[Sqrt[Surd[1/5, 5]+Surd[4/5, 5]], 10, 120][[1]] (* Harvey P. Dale, Dec 14 2021 *)
PROG
(PARI) sqrt((1/5)^(1/5)+(4/5)^(1/5))
CROSSREFS
Sequence in context: A011069 A010598 A152564 * A138029 A146481 A233766
KEYWORD
nonn,cons
AUTHOR
Hugo Pfoertner, Aug 28 2018
STATUS
approved