login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A156841 529n^2 - 312n + 46. 4
46, 263, 1538, 3871, 7262, 11711, 17218, 23783, 31406, 40087, 49826, 60623, 72478, 85391, 99362, 114391, 130478, 147623, 165826, 185087, 205406, 226783, 249218, 272711, 297262, 322871, 349538, 377263, 406046, 435887, 466786, 498743, 531758 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The identity (279841*n^2-165048*n+24335)^2-(529*n^2-312*n+46)*(12167*n-3588)^2=1 can be written as A156843(n)^2-a(n)*A156846(n)^2=1 for n>0.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

FORMULA

a(n) = 3*a(n-1) -3*a(n-2) +a(n-3).

G.f.: (46+125*x+887*x^2)/(1-x)^3.

MATHEMATICA

LinearRecurrence[{3, -3, 1}, {46, 263, 1538}, 40]

PROG

(MAGMA) I:=[46, 263, 1538]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..40]];

(PARI) a(n)=529*n^2-312*n+46 \\ Charles R Greathouse IV, Dec 23 2011

CROSSREFS

Cf. A156843, A156846, A156849.

Sequence in context: A251403 A026913 A244744 * A086979 A289274 A296402

Adjacent sequences:  A156838 A156839 A156840 * A156842 A156843 A156844

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Feb 17 2009

EXTENSIONS

Edited by Charles R Greathouse IV, Jul 25 2010

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 17 06:52 EDT 2019. Contains 327119 sequences. (Running on oeis4.)