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 A342931 #20 Mar 30 2021 01:18:54 %S A342931 1,7,13,511,1562,3013,411771,33554431,193710244,159687996, %T A342931 142655835305,2545864168851,151437553296126,4672524492952950, %U A342931 190419981278726,36893488147419103231,413620130943168382088,6624115793937660813847,989209827830156794561989,5961027129129868073483022,579547002657587965773234693 %N A342931 a(n) = A000217(A342930(n))/n^n. %o A342931 (PARI) a(n) = my(k=1, m=n^n); while(k*(k+1)/2%m!=0, k++); k*(k+1)/(2*m); %Y A342931 Cf. A000217, A000312, A232101, A342930. %K A342931 nonn,easy %O A342931 1,2 %A A342931 _Seiichi Manyama_, Mar 29 2021 %E A342931 More terms from _David A. Corneth_, Mar 29 2021