OFFSET
0,2
COMMENTS
Pronic residues (mod m) are analogous to quadratic residues.
Periodic with period 7.
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 1).
MATHEMATICA
Table[Mod[n^2+n, 7], {n, 0, 120}] (* Harvey P. Dale, Aug 26 2012 *)
LinearRecurrence[{0, 0, 0, 0, 0, 0, 1}, {0, 2, 6, 5, 6, 2, 0}, 105] (* Ray Chandler, Aug 26 2015 *)
PROG
(PARI) A053793(n)=[0, 2, 6, 5, 6, 2, 0][n%7+1] \\ - M. F. Hasler, Aug 27 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stuart M. Ellerstein (ellerstein(AT)aol.com), Mar 27 2000
EXTENSIONS
More terms from James A. Sellers, Apr 08 2000
STATUS
approved