OFFSET
0,3
COMMENTS
Periodic, with period = 14. - Harvey P. Dale, Jul 20 2021
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).
FORMULA
a(n) = a(n-28). - G. C. Greubel, Mar 24 2016
MATHEMATICA
Table[Mod[n^2, 28], {n, 0, 200}] (* Vladimir Joseph Stephan Orlovsky, Apr 27 2011 *)
PowerMod[Range[0, 100], 2, 28] (* or *) PadRight[{}, 100, {0, 1, 4, 9, 16, 25, 8, 21, 8, 25, 16, 9, 4, 1}] (* Harvey P. Dale, Jul 20 2021 *)
PROG
(PARI) a(n)=n^2%28 \\ Charles R Greathouse IV, Apr 06 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 12 2002
STATUS
approved