|
| |
|
|
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; 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 to sequences with 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: A160334 A083358 A026913 * A086979 A077734 A135735
Adjacent sequences: A156838 A156839 A156840 * A156842 A156843 A156844
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Feb 17 2009
|
|
|
EXTENSIONS
| Edited by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Jul 25 2010
|
| |
|
|
