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 A072038 #16 Apr 24 2024 11:11:31 %S A072038 1,1,2,1,1,2,1,1,3,1,2,2,2,1,1,1,3,2,1,1,1,1,3,2,3,4,1,1,2,1,3,1,1,2, %T A072038 2,2,1,1,1,4,2,3,2,1,1,1,1,4,2,1,1,1,3,1,1,4,2,2,1,1,2,1,3,1,2,5,1,1, %U A072038 3,2,3,1,4,1,2,2,3,1,1,1,1,1,2,3,1,1,1,5,2,1,1,3,2,1,4,2,2,1,1,1,2,1,1,5,1 %N A072038 Column of Zorach additive triangle in which n appears (or 0 in the unlikely event that it does not). %H A072038 Reinhard Zumkeller, <a href="/A072038/b072038.txt">Table of n, a(n) for n = 1..1000</a> %H A072038 A. C. Zorach, <a href="http://www.cazort.net/static/triangle.php">Additive triangle</a> %H A072038 <a href="/A035312/a035312_2.hs.txt">Haskell programs for sequences in connection with Zorach additive triangle</a> %F A072038 If a(n) > 0: n = A035312(A072039(n)-1, a(n)-1). %e A072038 a(8)=1 since 8 appears in the first (i.e. left hand) column. %o A072038 (Haskell) -- See link. %Y A072038 If a(n)=1 then n is in A035311, if a(n)=A072039(n) then n is in A035313. Cf. A035312, A035358, A072039. %K A072038 nonn %O A072038 1,3 %A A072038 _Henry Bottomley_, Jun 07 2002