This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A285733 #18 Jun 12 2025 12:58:39 %S A285733 -1,1,1,3,-2,2,6,2,3,4,10,5,-3,5,7,15,9,4,6,8,11,21,14,8,-4,9,12,16, %T A285733 28,20,13,7,10,13,17,22,36,27,19,12,-5,14,18,23,29,45,35,26,18,11,15, %U A285733 19,24,30,37,55,44,34,25,17,-6,20,25,31,38,46,66,54,43,33,24,16,21,26,32,39,47,56,78,65,53,42,32,23,-7,27,33,40,48,57,67 %N A285733 Transpose of square array A285732. %C A285733 See A285732. %H A285733 Antti Karttunen, <a href="/A285733/b285733.txt">Table of n, a(n) for n = 1..7260; the first 120 antidiagonals of the array</a> %F A285733 A(n,k) = A285732(k,n) = A285723(n,k) - A286100(n,k). %e A285733 The top left 9 X 9 corner of the array: %e A285733 -1, 1, 3, 6, 10, 15, 21, 28, 36 %e A285733 1, -2, 2, 5, 9, 14, 20, 27, 35 %e A285733 2, 3, -3, 4, 8, 13, 19, 26, 34 %e A285733 4, 5, 6, -4, 7, 12, 18, 25, 33 %e A285733 7, 8, 9, 10, -5, 11, 17, 24, 32 %e A285733 11, 12, 13, 14, 15, -6, 16, 23, 31 %e A285733 16, 17, 18, 19, 20, 21, -7, 22, 30 %e A285733 22, 23, 24, 25, 26, 27, 28, -8, 29 %e A285733 29, 30, 31, 32, 33, 34, 35, 36, -9 %o A285733 (Scheme) (define (A285733 n) (A285732bi (A004736 n) (A002260 n))) ;; For A285732bi see under A285732. %o A285733 (Python) %o A285733 def T(n, m): return ((n + m)**2 - n - 3*m + 2)//2 %o A285733 def A(n, k): return -n if n == k else T(n - k, k) if n>k else T(n, k - n) %o A285733 for n in range(1, 21): print([A(n - k + 1, k) for k in range(1, n + 1)]) # _Indranil Ghosh_, May 03 2017 %Y A285733 Transpose: A285732. %Y A285733 Cf. A285723, A286100. %K A285733 sign,tabl %O A285733 1,4 %A A285733 _Antti Karttunen_, May 03 2017