|
|
A111988
|
|
Greatest number having n quadratic residues, or 0 if there is no such number.
|
|
3
|
|
|
1, 4, 8, 16, 0, 24, 32, 48, 40, 19, 27, 80, 0, 96, 29, 144, 0, 120, 37, 76, 160, 108, 128, 240, 0, 0, 136, 288, 0, 152, 81, 336, 216, 67, 0, 360, 73, 148, 0, 304, 0, 480, 0, 432, 232, 384, 0, 720, 416, 0, 101, 103, 125, 440, 109, 672, 296, 0, 0, 464, 0, 324, 544, 1008, 0
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
Table of n, a(n) for n=1..65.
|
|
EXAMPLE
|
a(4)=16 because, of the five numbers having 4 quadratic residues (6,7,9,12,16), the greatest is 16.
|
|
MATHEMATICA
|
t=Table[Length[Union[Mod[Range[0, n/2]^2, n]]], {n, 10000}]; Table[pos=Flatten[Position[t, n]]; If[Length[pos]==0, 0, Last[pos]], {n, 100}]
|
|
CROSSREFS
|
Cf. A037046 (n such that a(n)=0), A111986 (number of numbers having n quadratic residues), A111987 (least number having n quadratic residues).
Sequence in context: A321500 A103536 A011970 * A110652 A059373 A137798
Adjacent sequences: A111985 A111986 A111987 * A111989 A111990 A111991
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
T. D. Noe, Aug 25 2005
|
|
STATUS
|
approved
|
|
|
|