A375851 Decimal expansion of the 7th root of 306.

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

Offset: 1

Author

Stefano Spezia, Sep 15 2024

Keywords

• nonn
• cons
• easy

Comments

Calculated to 2800 digits by R. William Gosper in a 1976 contest where this task was the problem number 9.

Examples

			2.26518178629569774774567213263272411892131...
		

References

• David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See pp. 151-152.

Links

• Fred Gruenberger, Contest 12: Countdown, Popular Computing, Vol. 4, No. 10 (1976), p. 10.
• Fred Gruenberger, Contest 12 results, Popular Computing, Vol. 5, No. 3 (1977), p. 6.
• Fred Gruenberger, Gosper, Popular Computing, Vol. 5, No. 5 (1977), p. 18.
• Fred Gruenberger, Computer Recreations, Scientific American, Vol. 250, No. 4 (1984), pp. 19-27.

Crossrefs

Cf. A010769, A011186, A011201, A011216, A011231, A011246, A011261, A011276, A011291, A011306, A011321, A011336, A011351, A011366, A011381, A011396, A011411, A011426.

Programs

Mathematica

RealDigits[306^(1/7),10,100][[1]]

PARI

sqrtn(306, 7) \\ Amiram Eldar, Sep 18 2024

Formula

Equals A010769*A011261*A011381. - R. J. Mathar, Sep 23 2024