cp's OEIS Frontend

A165916 Irregular triangle read by rows: squarefree quadratic non-residues.

%I A165916 #11 Aug 03 2014 14:01:25
%S A165916 2,2,3,2,3,2,5,3,5,6,2,3,5,6,7,2,3,5,6,2,3,7,2,6,7,10,2,3,5,6,7,10,11,
%T A165916 2,5,6,7,11,3,5,6,10,13,2,3,5,7,11,13,14,2,3,5,6,7,10,11,13,14,15,3,5,
%U A165916 6,7,10,11,14,2,3,5,6,11,14,15,17,2,3,10,13,14,15
%N A165916 Irregular triangle read by rows: squarefree quadratic non-residues.
%C A165916 The irregular triangle of numbers is:
%C A165916 ..n....Squarefree quadratic non-residues
%C A165916 ..1....
%C A165916 ..2....
%C A165916 ..3....2
%C A165916 ..4....2..3
%C A165916 ..5....2..3
%C A165916 ..6....2..5
%C A165916 ..7....3..5..6
%C A165916 ..8....2..3..5..6..7
%C A165916 ..9....2..3..5..6
%C A165916 .10....2..3..7
%C A165916 .11....2..6..7.10
%C A165916 .12....2..3..5..6..7.10.11
%C A165916 .13....2..5..6..7.11
%C A165916 .14....3..5..6.10.13
%C A165916 .15....2..3..5..7.11.13.14
%C A165916 .16....2..3..5..6..7.10.11.13.14.15
%C A165916 .17....3..5..6..7.10.11.14
%C A165916 .18....2..3..5..6.11.14.15.17
%C A165916 .19....2..3.10.13.14.15
%H A165916 C. H. Gribble, <a href="/A165916/b165916.txt">Flattened irregular triangle read by rows j = 3 to 200</a>
%t A165916 Flatten[Table[Select[Complement[Range[n - 1], Mod[Range[n/2]^2, n]], SquareFreeQ], {n, 3, 30}]] (* _T. D. Noe_, Nov 22 2011 *)
%Y A165916 Cf. A096013.
%K A165916 nonn,tabf
%O A165916 3,1
%A A165916 _Christopher Hunt Gribble_, Sep 30 2009
%E A165916 Minor edit by _Christopher Hunt Gribble_, Oct 05 2009