Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A157768
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A157768 a(n)=27225*n^2-39202*n+14112 (n>0) +0
3
2135, 44608, 141531, 292904, 498727, 759000, 1073723, 1442896, 1866519, 2344592, 2877115, 3464088, 4105511, 4801384, 5551707, 6356480, 7215703, 8129376, 9097499, 10120072, 11197095, 12328568, 13514491, 14754864, 16049687, 17398960 (list; graph; listen)
OFFSET

1,1

COMMENT

If A=[A157768] 27225*n.^2-39202*n +14112 (2135, 44608, 141531,.,); Y=[A157769] 8984250*n - 6468330 (2515920, 11500170, 20484420..,); X=[A157770] 1482401250*n^2-2134548900*n + 768398401 (116250751, 2428905601, 7706362951,.,), we have, for all terms, Pell's equation X^2-A*Y^2=1. Example: 116250751^2-2135 *2515920^2=1; 2428905601^2-44608*11500170^2=1.

LINKS

Edward Everett Withford, Pell Equation

Vincenzo Librandi, X^2-AY^2=1

Wolfram MathWorld, Pell Equation

FORMULA

a(n)=27225*n^2-39202*n+14112 (n>0)

EXAMPLE

For n=1, a(1)=2135; n=2, a(2)=44608; n=3, a(3)=141531

CROSSREFS

Cf. 157769, A157770

Sequence in context: A031544 A066817 A110024 this_sequence A067199 A064249 A020398

Adjacent sequences: A157765 A157766 A157767 this_sequence A157769 A157770 A157771

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.i), Mar 06 2009

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 December 2 11:54 EST 2009. Contains 167921 sequences.


AT&T Labs Research