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%I #6 May 01 2013 21:13:44
%S 4,4,4,4,4,4,9,4,9,4,9,4,9,12,4,8,9,4,9,4,9,4,8,9,16,4,9,16,4,9,16,4,
%T 9,16,4,9,16,18,4,9,12,16,20,4,8,9,12,16,18,4,9,12,16,4,9,16,24,4,9,
%U 12,16,25,4,9,16,25,4,8,9,16,25,4,9,16,20,24,25,28,4,9,16,24,25
%N Irregular triangle read by rows: square-full nonzero quadratic residues mod n.
%C The irregular triangle of numbers is:
%C ..n....Square-full nonzero quadratic residues
%C ..1....
%C ..2....
%C ..3....
%C ..4....
%C ..5.....4
%C ..6.....4
%C ..7.....4
%C ..8.....4
%C ..9.....4
%C .10.....4..9
%C .11.....4..9
%C .12.....4..9
%C .13.....4..9.12
%C .14.....4..8..9
%C .15.....4..9
%C .16.....4..9
%C .17.....4..8..9.16
%C .18.....4..9.16
%C .19.....4..9.16
%C .20.....4..9.16
%C .21.....4..9.16.18
%C .22.....4..9.12.16.20
%C .23.....4..8..9.12.16.18
%C .24.....4..9.12.16
%C .25.....4..9.16.24
%C .26.....4..9.12.16.25
%C .27.....4..9.16.25
%C .28.....4..8..9.16.25
%C .29.....4..9.16.20.24.25
%C .30.....4..9.16.24.25
%H C. H. Gribble, <a href="/A165919/b165919.txt">Flattened irregular triangle read by rows as table of j, a(j) for j = 5..69744 (rows 5:1000)</a>. [Entries in b-file edited by _N. J. A. Sloane_, Oct 04 2010]
%Y Cf. A046071.
%K nonn,tabf
%O 5,1
%A _Christopher Hunt Gribble_, Sep 30 2009
%E Minor edit and cross-reference added by _Christopher Hunt Gribble_, Oct 05 2009
%E Offset set to 5, keyword:tabf added - _R. J. Mathar_, Oct 09 2009