Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A023057
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A023057 (Apparently) not the difference between adjacent perfect powers (A001597, integers of form a^b, a >= 1, b >= 2). +0
8
6, 14, 22, 29, 31, 34, 42, 44, 46, 50, 52, 54, 58, 62, 64, 66, 70, 72, 78, 82, 84, 86, 88, 90, 91, 96, 98, 102, 105, 110, 111, 114, 117, 118, 120, 122, 124, 126, 130, 132, 134, 136, 140, 142, 153, 156, 158, 160, 162, 164, 165, 172, 176, 177, 178, 179, 181, 182, 188, 190 (list; graph; listen)
OFFSET

1,1

COMMENT

Catalan's conjecture (now a theorem) is that 1 occurs just once as a difference, between 8 and 9.

REFERENCES

G. Everest, A. van der Poorten, I. Shparlinski and T. Ward, Recurrence Sequences, Amer. Math. Soc., 2003; see esp. p. 255.

LINKS

Alf van der Poorten, Remarks on the sequence of 'perfect' powers

MATHEMATICA

pp = Union[ Join[{1}, Flatten[ Table[n^i, {n, 2, Sqrt[10^12]}, {i, 2, Log[n, 10^12]}]]]]; l = Length[pp]; d = Sort[Take[pp, -l + 1] - Take[pp, l - 1]]; Complement[ Table[i, {i, 1, 200}], Take[ Union[d], 200]] (from Robert G. Wilson v)

CROSSREFS

Cf. A001597 (perfect powers), A023055 (complement). See also A074980, A074981, A077286.

Sequence in context: A110223 A125086 A138290 this_sequence A062316 A079299 A043445

Adjacent sequences: A023054 A023055 A023056 this_sequence A023058 A023059 A023060

KEYWORD

nonn,nice

AUTHOR

David W. Wilson (davidwwilson(AT)comcast.net)

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified July 26 23:19 EDT 2008. Contains 142293 sequences.


AT&T Labs Research