cp's OEIS Frontend

A165913 Irregular triangle read by rows: Squarefree nonzero quadratic residues.

%I A165913 #7 Aug 10 2015 00:25:32
%S A165913 1,1,1,1,1,3,1,2,1,1,7,1,5,6,1,3,5,1,1,3,10,1,2,7,11,1,6,10,1,1,2,13,
%T A165913 15,1,7,10,13,1,5,6,7,11,17,1,5,1,7,15,1,3,5,11,14,15,1,2,3,6,13,1,1,
%U A165913 6,11,14,19,21,1,3,10,13,14,17,22,23,1,7,10,13,19,22,1,21,1,5,6,7,13,22,23
%N A165913 Irregular triangle read by rows: Squarefree nonzero quadratic residues.
%C A165913 The irregular triangle of numbers is:
%C A165913 ..n....Squarefree nonzero quadratic residues
%C A165913 ..1....
%C A165913 ..2....1
%C A165913 ..3....1
%C A165913 ..4....1
%C A165913 ..5....1
%C A165913 ..6....1..3
%C A165913 ..7....1..2
%C A165913 ..8....1
%C A165913 ..9....1..7
%C A165913 .10....1..5..6
%C A165913 .11....1..3..5
%C A165913 .12....1
%C A165913 .13....1..3.10
%C A165913 .14....1..2..7.11
%C A165913 .15....1..6.10
%C A165913 .16....1
%C A165913 .17....1..2.13.15
%C A165913 .18....1..7.10.13
%C A165913 .19....1..5..6..7.11.17
%C A165913 .20....1..5
%C A165913 .21....1..7.15
%C A165913 .22....1..3..5.11.14.15
%C A165913 .23....1..2..3..6.13
%C A165913 .24....1
%C A165913 .25....1..6.11.14.19.21
%C A165913 .26....1..3.10.13.14.17.22.23
%C A165913 .27....1..7.10.13.19.22
%C A165913 .28....1.21
%C A165913 .29....1..5..6..7.13.22.23
%H A165913 C. H. Gribble, <a href="/A165913/b165913.txt">Flattened irregular triangle read by rows as table of j, a(j) for j = 1: 78998 (rows 2:1000)</a>.
%Y A165913 Cf. A046071.
%K A165913 nonn,tabf
%O A165913 1,6
%A A165913 _Christopher Hunt Gribble_, Sep 30 2009
%E A165913 Minor edit by _Christopher Hunt Gribble_, Oct 05 2009