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0,3
G. C. Greubel, Table of n, a(n) for n = 0..1000
a(n) = a(n-28). - G. C. Greubel, Mar 24 2016
Table[Mod[n^2, 28], {n, 0, 200}] (* Vladimir Joseph Stephan Orlovsky, Apr 27 2011 *)
(PARI) a(n)=n^2%28 \\ Charles R Greathouse IV, Apr 06 2016
Cf. A070448, A070449.
Sequence in context: A070452 A070653 A070451 * A070449 A070448 A081403
Adjacent sequences: A070447 A070448 A070449 * A070451 A070452 A070453
nonn,easy
N. J. A. Sloane, May 12 2002
approved