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 A210948 #18 Mar 11 2015 07:27:08 %S A210948 1,2,4,4,6,9,7,13,16,20,12,20,26,30,35,19,35,47,55,60,66,30,52,70,82, %T A210948 92,98,105,45,83,110,134,149,161,168,176,67,119,164,196,221,239,253, %U A210948 261,270,97,179,242,294,334,364,385,401,410,420 %N A210948 Triangle read by rows: T(n,k) = sum of all parts <= k of all partitions of n. %C A210948 Row n lists the partial sums of row n of triangle A138785. %H A210948 Alois P. Heinz, <a href="/A210948/b210948.txt">Rows n = 1..141, flattened</a> %F A210948 T(n,k) = sum_{j=1..k} A138785(n,j). %e A210948 Triangle begins: %e A210948 1; %e A210948 2, 4; %e A210948 4, 6, 9; %e A210948 7, 13, 16, 20; %e A210948 12, 20, 26, 30, 35; %e A210948 19, 35, 47, 55, 60, 66; %e A210948 30, 52, 70, 82, 92, 98, 105; %e A210948 45, 83, 110, 134, 149, 161, 168, 176; %e A210948 67, 119, 164, 196, 221, 239, 253, 261, 270; %p A210948 p:= (f, g)-> zip((x, y)-> x+y, f, g, 0): %p A210948 b:= proc(n, i) option remember; local f, g; %p A210948 if n=0 then [1] %p A210948 elif i=1 then [1, n] %p A210948 else f:= b(n, i-1); g:= `if`(i>n, [0], b(n-i, i)); %p A210948 p (p (f, g), [0$i, g[1]*i]) %p A210948 fi %p A210948 end: %p A210948 T:= proc(n, k) option remember; %p A210948 b(n, n)[k+1] +`if`(k<2, 0, T(n, k-1)) %p A210948 end: %p A210948 seq (seq (T(n,k), k=1..n), n=1..12); # _Alois P. Heinz_, May 02 2012 %t A210948 p[f_, g_] := With[{m = Max[Length[f], Length[g]]}, PadRight[f, m, 0] + PadRight[g, m, 0]]; b[n_, i_] := b[n, i] = Module[{f, g}, Which[n == 0, {1}, i == 1, {1, n}, True, f = b[n, i-1]; g = If[i>n, {0}, b[n-i, i]]; p[p[f, g], Append[Array[0&, i], i*g[[1]]]]]]; T[n_, k_] := T[n, k] = b[n, n][[k+1]] + If[k<2, 0, T[n, k-1]]; Table[Table[T[n, k], {k, 1, n}], {n, 1, 12 }] // Flatten (* _Jean-François Alcover_, Mar 11 2015, after _Alois P. Heinz_ *) %Y A210948 Column 1 is A000070(n-1). Right border gives A066186. %Y A210948 Cf. A181187, A138785, A206561, A210948, A208475, A210956. %K A210948 nonn,tabl %O A210948 1,2 %A A210948 _Omar E. Pol_, May 01 2012