OFFSET
1,2
FORMULA
a(n)=n^6-A115223(n). For prime n, a(n)=(n^3-1)(n-1)n^2.
MATHEMATICA
Table[cnt=0; Do[m={{a, b, c}, {b, d, e}, {c, e, f}}; If[Det[m, Modulus->n]>0, cnt++ ], {a, 0, n-1}, {b, 0, n-1}, {c, 0, n-1}, {d, 0, n-1}, {e, 0, n-1}, {f, 0, n-1}]; cnt, {n, 2, 20}]
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jan 16 2006
STATUS
approved