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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.

A072083 Numbers divisible by the 4th power of the sum of their digits in base 10.

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%I A072083 #32 Nov 25 2022 22:26:20
%S A072083 1,10,100,1000,2000,2401,5000,10000,13122,20000,24010,50000,100000,
%T A072083 110000,131220,140000,190000,200000,230000,234256,240100,280000,
%U A072083 320000,370000,390625,400221,410000,460000,500000,512000,550000,614656,640000
%N A072083 Numbers divisible by the 4th power of the sum of their digits in base 10.
%C A072083 If k is a term, then 10*k is a term. There are an infinite number of terms that are not divisible by 10. The numbers m = 24 * 10^(294*k - 292) + 1, k = 7*a - 6, a >= 1, are divisible by 7^4 = digsum(m)^4. Also, the numbers s = 491 * 10^(4624*k - 4623) + 3, k = 17*u - 11, u >= 1, are divisible by 17^4 = digsum(s)^4. - _Marius A. Burtea_, Mar 19 2020
%C A072083 The numbers 2^A095412(n), n >= 6, are terms. - _Marius A. Burtea_, Apr 02 2020
%H A072083 Donovan Johnson, <a href="/A072083/b072083.txt">Table of n, a(n) for n = 1..1000</a>
%e A072083 k=614656: sumdigits(614656)=28, q=1, since k=28*28*28*28.
%t A072083 sud[x_] := Apply[Plus, IntegerDigits[x]] Do[s=sud[n]^4; If[IntegerQ[n/s], Print[n]], {n, 1, 10000}]
%t A072083 Select[Range[700000],Divisible[#,Total[IntegerDigits[ #]]^4]&] (* _Harvey P. Dale_, Jun 28 2011 *)
%o A072083 (Magma) [k:k in [1..640000]| k mod &+Intseq(k)^4 eq 0]; // _Marius A. Burtea_, Mar 19 2020
%o A072083 (PARI) isok(m) = (m % sumdigits(m)^4) == 0; \\ _Michel Marcus_, Apr 02 2020
%Y A072083 Cf. A005349, A003634, A072081, A072082.
%K A072083 base,nonn
%O A072083 1,2
%A A072083 _Labos Elemer_, Jun 14 2002