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 A330930 #16 Jan 05 2025 19:51:41
%S A330930 1,2,3,4,10000095,41441420,124324220,124324221,124324222,207207020,
%T A330930 233735070,331531220,350602590,409036350,414414020,467470110,
%U A330930 621621020,621621021,621621022,1030302012,1036035020,1051807710,1201800620,1243242020,1243242021,1243242022
%N A330930 Starts of runs of 7 consecutive Niven (or Harshad) numbers (A005349).
%C A330930 Cooper and Kennedy proved that there are infinitely many runs of 20 consecutive Niven numbers. Therefore this sequence is infinite.
%D A330930 Jean-Marie De Koninck, Those Fascinating Numbers, American Mathematical Society, 2009, p. 36, entry 110.
%H A330930 Amiram Eldar, <a href="/A330930/b330930.txt">Table of n, a(n) for n = 1..400</a>
%H A330930 Curtis Cooper and Robert E. Kennedy, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/31-2/cooper.pdf">On consecutive Niven numbers</a>, Fibonacci Quarterly, Vol. 21, No. 2 (1993), pp. 146-151.
%H A330930 Helen G. Grundman, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/32-2/grundman.pdf">Sequences of consecutive Niven numbers</a>, Fibonacci Quarterly, Vol. 32, No. 2 (1994), pp. 174-175.
%H A330930 Wikipedia, <a href="https://en.wikipedia.org/wiki/Harshad_number">Harshad number</a>.
%H A330930 Brad Wilson, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/35-2/wilson.pdf">Construction of 2n consecutive n-Niven numbers</a>, Fibonacci Quarterly, Vol. 35, No. 2 (1997), pp. 122-128.
%e A330930 10000095 is a term since 10000095 is divisible by 1 + 0 + 0 + 0 + 0 + 0 + 9 + 5 = 15, 10000096 is divisible by 16, ..., and 10000101 is divisible by 3.
%t A330930 nivenQ[n_] := Divisible[n, Total @ IntegerDigits[n]]; niv = nivenQ /@ Range[7]; seq = {}; Do[niv = Join[Rest[niv], {nivenQ[k]}]; If[And @@ niv, AppendTo[seq, k - 6]], {k, 7, 10^7}]; seq
%Y A330930 Cf. A005349, A060159, A141769, A154701, A330927, A330928, A330929.
%K A330930 nonn,base
%O A330930 1,2
%A A330930 _Amiram Eldar_, Jan 03 2020