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A164846
Triangle read by rows: frequency with which the number of values taken by cos(2*Pi/k) mod j occurs for each j >= 1, taken over k = 1..j-1.
5
0, 0, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 3, 0, 0, 0, 3, 0, 0, 1, 1, 0, 2, 3, 0, 1, 0, 0, 0, 4, 0, 0, 2, 0, 0, 1, 0, 3, 1, 1, 2, 0, 1, 0, 0, 0, 3, 2, 0, 1, 2, 0, 0, 1, 0, 0, 2, 5, 1, 1, 0, 1, 0, 0, 0, 0, 0, 6, 0, 0, 3, 0, 0, 0, 0, 0, 0, 2, 0, 3, 6, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 5, 2, 0, 2, 1, 0, 0, 1, 2, 0, 0, 0, 0
OFFSET
1,8
COMMENTS
See A164823 for explanatory comment and the definition of "cos(x) mod j".
LINKS
EXAMPLE
The triangle of numbers is:
..j....Frequency of numbers of solutions over k
.......0..1..2..3..4..5..6..7..8..9..10
..1....0
..2....0..1
..3....0..1..1
..4....0..2..1..0
..5....0..1..3..0..0
..6....0..3..0..0..1..1
..7....0..2..3..0..1..0..0
..8....0..4..0..0..2..0..0..1
..9....0..3..1..1..2..0..1..0..0
.10....0..3..2..0..1..2..0..0..1..0
.11....0..2..5..1..1..0..1..0..0..0..0
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
EXTENSIONS
Minor edits from N. J. A. Sloane, Sep 01 2009
Sequence corrected by Christopher Hunt Gribble, Sep 10 2009
Minor edits by Christopher Hunt Gribble, Oct 01 2009
STATUS
approved