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 A128222 #11 Feb 18 2022 22:08:13
%S A128222 1,1,2,3,1,3,1,4,1,4,5,1,5,1,5,1,6,1,6,1,6,7,1,7,1,7,1,7,1,8,1,8,1,8,
%T A128222 1,8,9,1,9,1,9,1,9,1,9,1,10,1,10,1,10,1,10,1,10
%N A128222 A127701 * A128174.
%C A128222 Row sums = A128223: (1, 3, 7, 10, 17, 21, 31, 36, ...).
%F A128222 A127701 * A128174 as infinite lower triangular matrices. Odd rows: n terms of n, 1, n, ...; even rows: n terms of 1, n, 1, ...
%e A128222 First few rows of the triangle:
%e A128222 1;
%e A128222 1, 2;
%e A128222 3, 1, 3;
%e A128222 1, 4, 1, 4;
%e A128222 5, 1, 5, 1, 5;
%e A128222 1, 6, 1, 6, 1, 6;
%e A128222 7, 1, 7, 1, 7, 1, 7;
%e A128222 ...
%t A128222 a128222[n_, k_] := If[EvenQ[n-k], n, 1]/;1<=k<=n
%t A128222 a128222[r_] := Table[a128222[n, k], {n, 1, r}, {k, 1, n}]
%t A128222 TableForm[a128222[7]] (* triangle *)
%t A128222 Flatten[a128222[10]] (* data *) (* _Hartmut F. W. Hoft_, Mar 08 2017 *)
%Y A128222 Cf. A127701, A128174, A128223, A128222.
%K A128222 nonn,tabl
%O A128222 1,3
%A A128222 _Gary W. Adamson_, Feb 19 2007
%E A128222 Inserted omitted values a(28) = 7 and a(29) = 1, _Hartmut F. W. Hoft_, Mar 08 2017