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 A083935 #6 Jan 30 2024 04:37:38 %S A083935 0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,0, %T A083935 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, %U A083935 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 %N A083935 Inverse function of N -> N injection A083934. %C A083935 a(0)=0 because A083934(0)=0, but a(n) = 0 also for those n which do not occur as values of A083934. All positive natural numbers occur here once. %o A083935 (MIT Scheme:) (define (A083935 n) (let* ((b (A014486 n)) (c (if (zero? (modulo b 3)) (A059905 (/ b 3)) 0))) (if (zero? (A059906 (/ b 3))) (A080300 c) 0))) %Y A083935 a(A080934(n)) = n for all n. Cf. A083925-A083929, A014486, A080300, A059905, A059906. %K A083935 nonn %O A083935 0,16 %A A083935 _Antti Karttunen_, May 13 2003