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 A045870 #12 Nov 13 2022 02:06:32 %S A045870 1,1,2,1,1,2,2,4,2,2,2,1,6,4,4,8,8,8,4,3,6,3,12,3,3,6,6,12,12,6,6,10, %T A045870 10,10,5,10,5,5,20,5,10,7,14,28,22,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, %U A045870 2,2,2,2,2,2,2,2,2,2,2,4,22,2,2,2,4,2,2,2,2,2,2,2,2,2,2,2,2,2,4,2,4,2,2 %N A045870 Number of times the digits are repeated in A045869. %H A045870 Naohiro Nomoto, <a href="https://web.archive.org/web/20000916012426/http://www.geocities.co.jp/Technopolis/1793/09digit.htm">In the list of divisors of n, ...</a> %e A045870 A045869(1) = 2034, and the divisors of 2034_5 = 269 (a prime) are 1 and 269; in base 5, these are 1 and 2034. Each digit from 0 through 4 appears exactly once, so a(1) = 1. %e A045870 A045869(2) = 2403; 2403_5 = 353 (a prime) has divisors 1 and 353, which in base 5 are 1 and 2403, so each digit in 0..4 appears exactly once, so a(2) = 2. %e A045870 A045869(3) = 2430; 2430_5 = 365 = 5*73, so its divisors are 1, 5, 73, and 365, which in base 5 are 1, 10, 243, and 2430, so each digit in 0..4 appears exactly twice, so a(3) = 2. %Y A045870 Cf. A038564, A038565, A045869. %K A045870 easy,nonn,base %O A045870 0,3 %A A045870 _Naohiro Nomoto_ %E A045870 Examples edited by _Jon E. Schoenfield_, Nov 12 2022