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 A331172 #7 Jan 12 2020 23:50:46 %S A331172 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,12,13,14,15,16,17,24,25, %T A331172 26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,42, %U A331172 43,44,45,46,47,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81 %N A331172 a(n) = min(n, A289234(n)), where A289234 is primorial base "reciprocal" flip. %C A331172 For all i, j: %C A331172 a(i) = a(j) => A267263(i) = A267263(j). %C A331172 For all i, j > 0: %C A331172 a(i) = a(j) => A053669(i) = A053669(j). %H A331172 Antti Karttunen, <a href="/A331172/b331172.txt">Table of n, a(n) for n = 0..30029</a> %H A331172 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a> %F A331172 a(n) = min(n, A289234(n)). %o A331172 (PARI) %o A331172 A289234(n) = { my(pr=1, p=2, v=0); while(n>0, my (d=n%p); if(d>0, v += pr * lift(1/Mod(d, p))); pr *= p; n \= p; p = nextprime(p+1)); return(v); }; \\ From A289234. %o A331172 A331172(n) = min(n, A289234(n)); %Y A331172 Cf. A053669, A267263, A289234. %Y A331172 Cf. also A286626, A328477, A330740, A331171. %K A331172 nonn,base %O A331172 0,3 %A A331172 _Antti Karttunen_, Jan 12 2020