|
| |
|
|
A159469
|
|
Maximum remainder when (a + 1)^n + (a - 1)^n is divided by a^2 for variable n and a>2.
|
|
1
| |
|
|
6, 8, 20, 24, 42, 48, 72, 80, 110, 120, 156, 168, 210, 224, 272, 288, 342, 360, 420, 440, 506, 528, 600, 624, 702, 728, 812, 840, 930, 960, 1056, 1088, 1190, 1224, 1332, 1368, 1482, 1520, 1640, 1680, 1806, 1848, 1980, 2024, 2162, 2208, 2352, 2400, 2550, 2600
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 3,1
|
|
|
LINKS
| Project Euler, Problem 120
|
|
|
FORMULA
| maxr(a) = a*a - 2*a if a is even = a*a - a if a is odd
Conjecture: G.f.: x^3*(-6-2*x)/((x+1)^2*(x-1)^3) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 26 2009]
Conjecture: a(n)=2*A050187(n). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 08 2009]
|
|
|
EXAMPLE
| for a = 3 maxr => 3*3 - 3 = 6 since 3 is odd for a = 4 maxr => 4*4 - 2*4 = 8 since 4 is even
|
|
|
CROSSREFS
| Sequence in context: A028331 A113806 A105775 * A191697 A096524 A083595
Adjacent sequences: A159466 A159467 A159468 * A159470 A159471 A159472
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Gaurav Kumar (gaurav.kumar.cse06(AT)itbhu.ac.in), Apr 13 2009
|
| |
|
|
