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%I

%S 8,8,8,8,8,12,8,12,8,12,12,8,12,8,12,18,8,12,18,8,12,20,8,18,20,8,18,

%T 20,8,12,18,20,8,18,20,24,8,12,18,20,24,12,18,20,24,27,8,12,18,27,8,

%U 12,18,20,27,28,12,24,27,8,12,18,20,24,27,28,8,18,20,24,28,32,12,20,24,27,28

%C The irregular triangle of numbers is:

%C ..1....

%C ..2....

%C ..3....

%C ..4....

%C ..5....

%C ..6....

%C ..7....

%C ..8....

%C ..9.....8

%C .10.....8

%C .11.....8

%C .12.....8

%C .13.....8

%C .14....12

%C .15.....8.12

%C .16.....8.12

%C .17....12

%C .18.....8.12

%C .19.....8.12.18

%C .20.....8.12.18

%C .21.....8.12.20

%C .22.....8.18

%C .23....20

%C .24.....8.18.20

%C .25.....8.12.18.20

%C .26.....8.18.20.24

%C .27.....8.12.18.20.24

%C .28....12.18.20.24.27

%C .29.....8.12.18.27

%C .30.....8.12.18.20.27.28

%C .31....12.24.27

%C .32.....8.12.18.20.24.27.28

%C .33.....8.18.20.24.28.32

%C .34....12.20.24.27.28

%H C. H. Gribble, <a href="/A165925/b165925.txt">Flattened irregular triangle read by rows j = 9 to 200</a>

%t Flatten[Table[Select[Complement[Range[n - 1], Mod[Range[n/2]^2, n]], ! SquareFreeQ[#] &], {n, 9, 34}]] (* _T. D. Noe_, Nov 22 2011 *)

%Y Cf. A096013.

%K nonn,tabf

%O 9,1

%A _Christopher Hunt Gribble_, Sep 30 2009

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Last modified October 14 15:03 EDT 2019. Contains 328019 sequences. (Running on oeis4.)