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 A343680 #20 Apr 28 2021 06:11:26 %S A343680 1,2,3,4,5,6,7,8,9,12,18,21,24,27,36,42,45,48,54,63,72,81,84,108,135, %T A343680 198,216,324,648,1008,1035,1050,1152,1215,1344,1380,1680,1725,2016, %U A343680 2376,2592,2625,2688,2997,3675,3816,3888,5616,5670,6912,10008,10017,10035,10044 %N A343680 Niven (or Harshad) numbers which when divided by sum of their digits, give a quotient which is a Zuckerman number. %C A343680 The first 24 terms of A114440 are the first 24 terms of this sequence, then A114440(25) = 162, while a(25) = 135. %H A343680 Giovanni Resta, <a href="https://www.numbersaplenty.com/set/Zuckerman_number/">Zuckerman Numbers</a>, Numbers Aplenty. %e A343680 84 is a Niven number as 84/(8+4) = 7, 7/7 = 1 so 7 is a Zuckerman number, and 84 is a term. %e A343680 108 is a Niven number as 108/(1+0+8) = 12, 12/(1*2) = 6 so 12 is a Zuckerman number, and 108 is a term. %t A343680 zuckQ[n_] := IntegerQ[n] && (prod = Times @@ IntegerDigits[n]) > 0 && Divisible[n, prod]; Select[Range[10^4], zuckQ[#/Plus @@ IntegerDigits[#]] &] (* _Amiram Eldar_, Apr 26 2021 *) %o A343680 (PARI) isz(n) = my(p=vecprod(digits(n))); p && !(n % p); \\ A007602 %o A343680 isok(n) = my(s=sumdigits(n)); !(n%s) && isz(n/s); \\ _Michel Marcus_, Apr 26 2021 %Y A343680 Cf. A005349, A007602, A114440, A235507. %K A343680 nonn,base %O A343680 1,2 %A A343680 _Bernard Schott_, Apr 26 2021 %E A343680 More terms from _Michel Marcus_, Apr 26 2021