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 A111948 #6 Oct 27 2019 11:12:09 %S A111948 24,42,114,222,402,2022,2202,7588,8596,10014,11202,12102,17668,21102, %T A111948 27748,29764,31002,32788,39844,42868,43876,45388,46396,48916,49924, %U A111948 55972,56476,57484,58492,65548,66556,69076,70588,71596,78148,81676 %N A111948 Admirable Harshad numbers n such that the subtracted divisor is equal to the digital sum of n. %H A111948 Amiram Eldar, <a href="/A111948/b111948.txt">Table of n, a(n) for n = 1..10000</a> %e A111948 a(2)=42 because 1+2+3+7+14+21-6 = 42 and 42/6 = 7. %t A111948 harsQ[n_] := Divisible[n, Plus @@ IntegerDigits[n]]; admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && Plus @@ IntegerDigits[n] == ab/2 && ab/2 < n && Divisible[n, ab/2]; Select[Range[100000], harsQ[#] && admQ[#] &] (* _Amiram Eldar_, Oct 27 2019 *) %Y A111948 Cf. A111592, A005349, A111947. %K A111948 base,nonn %O A111948 1,1 %A A111948 _Jason Earls_, Aug 22 2005