A011072 Decimal expansion of 4th root of 80.

2, 9, 9, 0, 6, 9, 7, 5, 6, 2, 4, 4, 2, 4, 4, 1, 0, 8, 3, 8, 2, 3, 7, 9, 7, 9, 8, 8, 2, 8, 1, 8, 2, 6, 7, 9, 0, 7, 2, 6, 9, 1, 9, 5, 1, 5, 2, 2, 9, 4, 1, 2, 6, 9, 1, 0, 3, 3, 1, 8, 7, 0, 0, 0, 0, 9, 5, 8, 4, 2, 9, 3, 3, 9, 4, 5, 9, 9, 4, 0, 2, 5, 6, 9, 7, 2, 4, 8, 8, 5, 1, 4, 1, 4, 9, 7, 6, 9, 5

Offset

1,1

Links

Ivan Panchenko, Table of n, a(n) for n = 1..1000

Amrik Singh Nimbran, Interesting infinite products of rational functions motivated by Euler, Math. Student, Vol. 85 (2016), pp. 117-133; ResearchGate link.

Index entries for algebraic numbers, degree 4.

Formula

Equals 2 * A011003. - Amiram Eldar, May 25 2023

Equals Product_{k>=1} (10*k-5)^2*(20*k-17)*(20*k-13)/((10*k-7)*(10*k-3)*(20*k-19)*(20*k-11)) (Nimbran, 2016, p. 131, eq. (65)). - Amiram Eldar, Jun 28 2026

Example

2.99069756244244108382379798828182679072691951522941...

Mathematica

RealDigits[Surd[80, 4], 10, 120][[1]] (* Harvey P. Dale, Nov 02 2015 *)

Prog

(PARI) sqrtn(80, 4) \\ Charles R Greathouse IV, Apr 16 2014

Crossrefs

Cf. A011003.

Sequence in context: A104954 A389930 A244292 * A175295 A198141 A395213

Adjacent sequences: A011069 A011070 A011071 * A011073 A011074 A011075

Keyword

nonn,cons,changed

Author

N. J. A. Sloane

Status

approved