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 A339146 #15 Nov 26 2020 23:21:39 %S A339146 1,1,1,1,1,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,2,4,6,8, %T A339146 10,3,6,9,12,15,4,8,12,16,20,5,10,15,20,25,1,2,3,4,5,2,4,6,8,10,3,6,9, %U A339146 12,15,4,8,12,16,20,5,10,15,20,25,1,2,3,4,5,2,4,6,8,10,3,6,9,12,15,4,8,12,16,20,5,10,15,20,25 %N A339146 a(n) = a(floor(n / 5)) * (n mod 5 + 1); initial terms are 1. %C A339146 If a(n) is arranged in a table with row lengths 5, then the first column is the transpose of the first row, followed the transpose of the second row, followed by the transpose of the third row, and so on. The remainder of each row (except the first) is an arithmetic progression whose start and step size equals the first entry of the row. %C A339146 a(n) = O(n). %C A339146 limsup_n a(n) = +oo. %e A339146 a(10) = a(2) * 1 = 1. %e A339146 a(13) = a(2) * 4 = 4. %o A339146 (Python) %o A339146 def a(n): %o A339146 if n < 5: %o A339146 return 1 %o A339146 q, r = divmod(n, 5) %o A339146 return a(q) * (r + 1) %o A339146 (PARI) a(n) = if (n < 5, 1, a(n\5)*(n % 5 + 1)); \\ _Michel Marcus_, Nov 26 2020 %Y A339146 Cf. A194459. %Y A339146 Cf. A048896 (with 2 instead of 5, but shifted). %K A339146 nonn %O A339146 0,7 %A A339146 _Robert Dougherty-Bliss_, Nov 25 2020