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 A048158 #51 Feb 16 2025 08:32:39 %S A048158 0,0,0,0,1,0,0,0,1,0,0,1,2,1,0,0,0,0,2,1,0,0,1,1,3,2,1,0,0,0,2,0,3,2, %T A048158 1,0,0,1,0,1,4,3,2,1,0,0,0,1,2,0,4,3,2,1,0,0,1,2,3,1,5,4,3,2,1,0,0,0, %U A048158 0,0,2,0,5,4,3,2,1,0,0,1,1,1,3,1,6,5,4,3,2,1,0,0,0,2,2,4,2,0,6,5,4,3,2,1,0 %N A048158 Triangular array T read by rows: T(n,k) = n mod k, for k=1,2,...,n, n=1,2,... %C A048158 Also, rectangular array read by antidiagonals: a(n, k) = n mod k, n >= 0, k >= 1. Cf. A051126, A051127, A051777. - _David Wasserman_, Oct 01 2008 %H A048158 Alois P. Heinz, <a href="/A048158/b048158.txt">Rows n = 1..141, flattened</a> %H A048158 Michael Z. Spivey, <a href="http://www.jstor.org/stable/30044176">The Humble Sum of Remainders Function</a>, Mathematics Magazine, Vol. 78, No. 4 (Oct., 2005), pp. 300-305. %H A048158 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Mod.html">Mod</a>. %F A048158 A051731(n,k) = A000007(T(n,k)). - _Reinhard Zumkeller_, Nov 01 2009 %F A048158 T(n,k) = n - k*A010766(n,k). - _Mats Granvik_, _Gary W. Adamson_, Feb 20 2010 %F A048158 G.f. for the k-th column: x^(k+1)*Sum_{i=0..k-2} (i + 1)*x^i/(1 - x^k). - _Stefano Spezia_, May 08 2024 %e A048158 Triangle begins %e A048158 0; %e A048158 0 0; %e A048158 0 1 0; %e A048158 0 0 1 0; %e A048158 0 1 2 1 0; %e A048158 0 0 0 2 1 0; %e A048158 0 1 1 3 2 1 0; %e A048158 0 0 2 0 3 2 1 0; %e A048158 0 1 0 1 4 3 2 1 0; %e A048158 0 0 1 2 0 4 3 2 1 0; %e A048158 0 1 2 3 1 5 4 3 2 1 0; %e A048158 0 0 0 0 2 0 5 4 3 2 1 0; %e A048158 ... %e A048158 From _Omar E. Pol_, Feb 21 2014: (Start) %e A048158 Illustration of the 12th row of triangle: %e A048158 ----------------------------------- %e A048158 . k: 1 2 3 4 5 6 7 8 9 10..12 %e A048158 ----------------------------------- %e A048158 . _ _ _ _ _ _ _ _ _ _ _ _ %e A048158 . |_| | | | | | | | | | | | %e A048158 . |_|_| | | | | | | | | | | %e A048158 . |_| |_| | | | | | | | | | %e A048158 . |_|_| |_| | | | | | | | | %e A048158 . |_| | | |_| | | | | | | | %e A048158 . |_|_|_| | |_| | | | | | | %e A048158 . |_| | | | | |_| | | | | | %e A048158 . |_|_| |_| | |*|_| | | | | %e A048158 . |_| |_| | | |* *|_| | | | %e A048158 . |_|_| | |_| |* * *|_| | | %e A048158 . |_| | | |*| |* * * *|_| | %e A048158 . |_|_|_|_|*|_|* * * * *|_| %e A048158 . %e A048158 Row 12 is 0 0 0 0 2 0 5 4 3 2 1 0 %e A048158 (End) %p A048158 T:= (n, k)-> modp(n, k): %p A048158 seq(seq(T(n, k), k=1..n), n=1..20); # _Alois P. Heinz_, Apr 04 2012 %t A048158 Flatten[Table[Mod[n, Range[n]], {n, 15}]] %o A048158 (Haskell) %o A048158 a048158 = mod %o A048158 a048158_row n = a048158_tabl !! (n-1) %o A048158 a048158_tabl = zipWith (map . mod) [1..] a002260_tabl %o A048158 -- _Reinhard Zumkeller_, Apr 29 2015, Jan 20 2014 (fixed), Aug 13 2013 %o A048158 (Python) %o A048158 def A048158_T(n,k): return n%k # _Chai Wah Wu_, May 13 2024 %Y A048158 Row sums are given by A004125. %Y A048158 Cf. A002260. %Y A048158 Cf. A000007, A010766, A051126, A051127, A051731, A051777. %K A048158 nonn,tabl %O A048158 1,13 %A A048158 _Clark Kimberling_ %E A048158 More terms from _David Wasserman_, Oct 01 2008