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 A358256 #20 Nov 06 2022 07:49:08 %S A358256 1,110,1300,17000,790000,59900000,19999999000000, %T A358256 2999999999999990000000,4999999999999999999999999999900000000, %U A358256 899999999999999999999999999999999999999999999999999999999000000000 %N A358256 a(n) is the smallest primitive Niven number ending with n zeros. %C A358256 1 is a primitive Niven number, not ending with 0, so a(0)=1. %C A358256 a(n) is the smallest term of A358255 that ends with n zeros for n > 0. %H A358256 Giovanni Resta, <a href="https://www.numbersaplenty.com/set/Harshad_number/">Harshad numbers</a>. %F A358256 a(n) = A051885(2^n)*10^n for n > 3. - _Rémy Sigrist_, Nov 05 2022 %e A358256 1300 is divisible by 1+3=4, but 13 and 130 are not divisible by 4; 1300 is the smallest such integer ending with two 0's, so a(2) = 1300. %Y A358256 Cf. A005349, A051885, A358255. %K A358256 nonn,base %O A358256 0,2 %A A358256 _Bernard Schott_, Nov 05 2022