A164831 a(n) is the number of values taken by cos(2*Pi/k) mod n for all k in 1..n-1.

0, 1, 3, 4, 7, 12, 12, 19, 22, 29, 25, 40, 29, 48, 59, 85, 42, 83, 53, 93, 99, 96, 64, 175, 144, 113, 159, 161, 97, 235, 100, 297, 187, 165, 231, 274, 111, 200, 224, 386, 156, 398, 149, 303, 425, 248, 152, 733, 450, 513, 332, 359, 181, 572, 448, 648, 384, 361, 221, 786

Offset: 1

Author

Christopher Hunt Gribble, Aug 27 2009

Keywords

• nonn

Comments

See A164823 for explanatory comment and the definition of "cos(x) mod j".

Links

• Christopher Hunt Gribble, Table of n, a(n) for n = 1..1000.

Crossrefs

Cf. A164822, A164823, A164846, A165252.

Extensions

Edited by N. J. A. Sloane, Sep 01 2009

Sequence corrected by Christopher Hunt Gribble, Sep 10 2009