|
| |
|
|
A046630
|
|
Number of cubic residues mod 2^n.
|
|
5
| |
|
|
1, 2, 3, 5, 10, 19, 37, 74, 147, 293, 586, 1171, 2341, 4682, 9363, 18725, 37450, 74899, 149797, 299594, 599187, 1198373, 2396746, 4793491, 9586981, 19173962, 38347923, 76695845, 153391690, 306783379, 613566757, 1227133514, 2454267027
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
LINKS
| S. R. Finch and Pascal Sebah, Squares and Cubes Modulo n (arXiv:math.NT/0604465).
Index to sequences with linear recurrences with constant coefficients, signature (2,0,1,-2)
|
|
|
FORMULA
| G.f.: (-2x^3-x^2+1)/[(1-2x)(1-x^3)].
a(n) = A046530(2^n) = 2^(n+2)/7 + 2/3 - (5*A049347(n)+A049347(n-1))/21. - R. J. Mathar, Feb 27 2011
|
|
|
MAPLE
| A049347 := proc(n) op( (n mod 3)+1, [1, -1, 0]) ; end proc:
A046630 := proc(n) 2^(n+2)/7+2/3-(5*A049347(n)+A049347(n-1))/21 ; end proc: # R. J. Mathar, Feb 27 2011
|
|
|
CROSSREFS
| Sequence in context: A065053 A078715 A166874 * A177874 A064236 A007569
Adjacent sequences: A046627 A046628 A046629 * A046631 A046632 A046633
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| David W. Wilson (davidwwilson(AT)comcast.net)
|
| |
|
|
