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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. 9
 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, 27, 28, 29, 30, 31, 32, 33, 34, 35, 40, 36, 37, 38, 39, 41, 42, 43, 44, 49, 45, 46, 47, 48, 50, 51, 52, 53, 54, 64, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 75, 66, 67, 68, 69, 70, 71 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 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. LINKS CROSSREFS Cf. A074132, A074133, A074134, A074136. Cf. A082017, A082018, A082019, A082020. Sequence in context: A166266 A011295 A082016 * A074146 A262478 A236348 Adjacent sequences:  A074132 A074133 A074134 * A074136 A074137 A074138 KEYWORD nonn,easy,tabl,less AUTHOR Amarnath Murthy, Aug 27 2002 EXTENSIONS Edited and extended by David Wasserman, Oct 31 2006 Further edited by N. J. A. Sloane Jan 17 2009 at the suggestion of R. J. Mathar STATUS approved

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Last modified May 21 08:31 EDT 2022. Contains 353898 sequences. (Running on oeis4.)