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A074135 Triangle read by rows: for 1 <= k < n, a(n, k) is the least positive integer not already used. a(n, n) is the least positive integer not already used that makes the row sum a multiple of n.

%I A074135 #6 Dec 05 2013 19:55:33
%S A074135 1,2,4,3,5,7,6,8,9,13,10,11,12,14,18,15,16,17,19,20,21,22,23,24,25,26,
%T A074135 27,28,29,30,31,32,33,34,35,40,36,37,38,39,41,42,43,44,49,45,46,47,48,
%U A074135 50,51,52,53,54,64,55,56,57,58,59,60,61,62,63,65,75,66,67,68,69,70,71
%N A074135 Triangle read by rows: for 1 <= k < n, a(n, k) is the least positive integer not already used. a(n, n) is the least positive integer not already used that makes the row sum a multiple of n.
%C A074135 Alternative (but equivalent) definition: In the following square array, numbers (not occurring earlier) are entered like this a(1, 1), a(1, 2), a(2, 1), a(3, 1), a(2, 2), a(1, 3), a(1, 4), a(2, 3), a(3, 2), a(4, 1), a(5, 1), a(4, 2), ... such that the n-th diagonal sum is a multiple of n. 1 2 7 6 18... 4 5 8 14... 3 9 12... 13 11... 10... ... sequence contains terms as they are entered.
%Y A074135 Cf. A074132, A074133, A074134, A074136.
%Y A074135 Cf. A082017, A082018, A082019, A082020.
%K A074135 nonn,easy,tabl,less
%O A074135 1,2
%A A074135 _Amarnath Murthy_, Aug 27 2002
%E A074135 Edited and extended by _David Wasserman_, Oct 31 2006
%E A074135 Further edited by _N. J. A. Sloane_ Jan 17 2009 at the suggestion of R. J. Mathar