login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A158135 a(n) = 144*n^2 - 2*n. 2
142, 572, 1290, 2296, 3590, 5172, 7042, 9200, 11646, 14380, 17402, 20712, 24310, 28196, 32370, 36832, 41582, 46620, 51946, 57560, 63462, 69652, 76130, 82896, 89950, 97292, 104922, 112840, 121046, 129540, 138322, 147392, 156750, 166396 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The identity (144*n - 1)^2 - (144*n^2 - 2*n)*12^2 = 1 can be written as A158136(n)^2 - a(n)*12^2 = 1. - Vincenzo Librandi, Feb 11 2012
LINKS
E. J. Barbeau, Polynomial Excursions, Chapter 10: Diophantine equations (2010), pages 84-85 (row 15 in the first table at p. 85, case d(t) = t*(12^2*t-2)).
FORMULA
G.f.: x*(-142 - 146*x)/(x-1)^3. - Vincenzo Librandi, Feb 11 2012
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Vincenzo Librandi, Feb 11 2012
MATHEMATICA
LinearRecurrence[{3, -3, 1}, {142, 572, 1290}, 50] (* Vincenzo Librandi, Feb 11 2012 *)
PROG
(Magma) I:=[142, 572, 1290]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..50]]; // Vincenzo Librandi, Feb 11 2012
(PARI) for(n=1, 50, print1(144*n^2 - 2*n", ")); \\ Vincenzo Librandi, Feb 11 2012
CROSSREFS
Cf. A158136.
Sequence in context: A035702 A172335 A217531 * A092230 A259422 A219146
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 13 2009
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 17:39 EDT 2024. Contains 371797 sequences. (Running on oeis4.)