login
A046459
Dudeney numbers: integers equal to the sum of the digits of their cubes.
14
0, 1, 8, 17, 18, 26, 27
OFFSET
1,3
COMMENTS
This sequence was first found by the French mathematician Claude (Séraphin) Moret-Blanc in 1879. See Le Lionnais page 27 for the last term of this sequence: 27. - Bernard Schott, Dec 07 2012
The name "Dudeney numbers" appears in the October 2018 issue of Mathematics Teacher (see link). - N. J. A. Sloane, Oct 10 2018
REFERENCES
H. E. Dudeney, 536 Puzzles & Curious Problems, reprinted by Souvenir Press, London, 1968, p. 36, #120.
Italo Ghersi, Matematica dilettevole e curiosa, p. 115, Hoepli, Milano, 1967. [From Vincenzo Librandi, Jan 02 2009]
F. Le Lionnais, Les nombres remarquables, Hermann, 1983.
J. Roberts, Lure of the Integers, The Mathematical Association of America, 1992, p. 172.
David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 96.
LINKS
The Mathematics Teacher, October 2018 Calendar and Solutions, Volume 112, Number 2, October 2018, pages 120 and 122.
Bernard Schott and Norbert Verdier, QDL 19: Quels beaux cubes! (French mathematical forum les-mathematiques.net).
Eric Weisstein's World of Mathematics, Cubic Number.
EXAMPLE
a(3) = 8 because 8^3 = 512 and 5 + 1 + 2 = 8.
a(7) = 27 because 27^3 = 19683 and 1 + 9 + 6 + 8 + 3 = 27.
MATHEMATICA
Select[Range[0, 30], #==Total[IntegerDigits[#^3]]&] (* Harvey P. Dale, Dec 21 2014 *)
PROG
(Magma) [n: n in [0..100] | &+Intseq(n^3) eq n ]; // Vincenzo Librandi, Sep 16 2015
(Python) a = [n for n in range(100) if sum(map(int, str(n ** 3))) == n] # David Radcliffe, Aug 18 2022
CROSSREFS
KEYWORD
base,fini,full,nonn
AUTHOR
Patrick De Geest, Aug 15 1998
EXTENSIONS
Offset corrected by Arkadiusz Wesolowski, Aug 09 2013
STATUS
approved