Tables of best known results on Taxicab and Cabtaxi numbers, in May 2007
(Tables built when the JIS & PLS articles were written in 2007. Today, better bounds are known: see the updated tables.)


We knew in November 2006:

Nothing seemed to be known on bigger n. I proposed to extend the range of known information on these numbers, with:

The upper bounds of Taxicab(7) and Cabtaxi(10) may have a chance of being the correct Taxicab and Cabtaxi numbers. But the probability decreases when n increases, and is close to 0 for Taxicab(19) and Cabtaxi(30).

(*) probability greater than 99.8%, according to a paper of 2005 by C. S. Calude - E. Calude - M. J. Dinneen, http://www.cs.auckland.ac.nz/CDMTCS/researchreports/261cris.pdf

Taxicab(2)

= 1729

Bernard Frenicle de Bessy
(France)

1657

Taxicab(3)

= 87539319

John Leech (UK)

1957

Taxicab(4)

= 6963472309248

Edwin Rosenstiel, John A. Dardis,
Colin R. Rosenstiel (UK)

1989

Taxicab(5)

= 48988659276962496

John A. Dardis (UK)

1994

Taxicab(6)

≤ 24153319581254312065344

Randall L. Rathbun (USA)

2002

Taxicab(7)

≤ 24885189317885898975235988544

: - )     (France)

Dec. 2006

Taxicab(8)

≤ 50974398750539071400590819921724352

Taxicab(9)

≤ 136897813798023990395783317207361432493888

Taxicab(10)

≤ 7335345315241855602572782233444632535674275447104

Taxicab(11)

≤ 2818537360434849382734382145310807703728251895897826621632

Taxicab(12)

≤ 73914858746493893996583617733225161086864012865017882136931801625152

Taxicab(13)
...
Taxicab(19)

see List 3 in the Appendix of the JIS paper
or the downloadable file at the end of this web page

May 2007

 

Cabtaxi(2)

= 91

François Viète (France),
Pietro Bongo (Italy) indep.

1591

Cabtaxi(3)

= 728

Edward B. Escott (USA)

1902

Cabtaxi(4)

= 2741256

Randall L. Rathbun (USA)

~1992

Cabtaxi(5)

= 6017193

Cabtaxi(6)

= 1412774811

Cabtaxi(7)

= 11302198488

Cabtaxi(8)

= 137513849003496

Daniel. J. Bernstein (USA)

1998

Cabtaxi(9)

= 424910390480793000

Duncan Moore (UK)

2005

Cabtaxi(10)

≤ 933528127886302221000

: - )     (France)

Dec. 2006 -
Feb. 2007

Cabtaxi(11)

≤ 8904950890305189093226944

Cabtaxi(12)

≤ 1912223147184127402358643000

Cabtaxi(13)

≤ 23266019031789278104497609381000

Cabtaxi(14)

≤ 567434938166308703690592195193209000

Cabtaxi(15)

≤ 31136289927061691188910174934641764248000

Cabtaxi(16)

≤ 1577146493675455843791867090964409284453944000

Cabtaxi(17)

≤ 23045156159180392847591977008030799542699242304000

Cabtaxi(18)

≤ 181609634582880844694340486417510510845396106201660096000

Cabtaxi(19)

≤ 298950477236981197723488725070538575992924211134299879660632000

Cabtaxi(20)

≤ 2149172021033860338362430683389430843511963750524516489973424104024000

Cabtaxi(21)
...
Cabtaxi(30)

see List 4 in the Appendix of the JIS paper
or the downloadable file at the end of this web page

May 2007

Warning! These numbers are no more the best known bounds! See the updated tables of Taxicab and Cabtaxi numbers.

Decompositions of these upper bounds:

And list of bigger upper bounds:

 Warning! Several numbers in the above lists of 2007 are no more the best known bounds! See the updated lists.