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A058903 Inconsummate numbers in base 7: no number is this multiple of the sum of its digits (in base 7).

%I A058903 #17 May 10 2023 12:18:19
%S A058903 30,86,102,134,138,141,158,162,167,170,183,186,194,210,213,233,284,
%T A058903 290,306,312,314,326,330,338,354,362,366,368,428,452,480,530,534,536,
%U A058903 540,542,554,564,578,591,602,645,648,656,705,708,714,740,746
%N A058903 Inconsummate numbers in base 7: no number is this multiple of the sum of its digits (in base 7).
%H A058903 Vincenzo Librandi, <a href="/A058903/b058903.txt">Table of n, a(n) for n = 1..10214</a>
%p A058903 For Maple code see A058906.
%t A058903 base=7; Do[k=n; While[Apply[Plus, IntegerDigits[k, base]] n!=k&&k<250n, k+=n]; If[k==250 n, Print[n]], {n, 1, 10^3}] (* _Vincenzo Librandi_, Jan 30 2017 *)
%o A058903 (Python)
%o A058903 from itertools import count, islice, combinations_with_replacement
%o A058903 from sympy.ntheory import digits
%o A058903 def A058903_gen(startvalue=1): # generator of terms >= startvalue
%o A058903     for n in count(max(startvalue,1)):
%o A058903         for l in count(1):
%o A058903             if 6*l*n < 7**(l-1):
%o A058903                 yield n
%o A058903                 break
%o A058903             for d in combinations_with_replacement(range(7),l):
%o A058903                 if (s:=sum(d)) > 0 and sorted(digits(s*n,7)[1:]) == list(d):
%o A058903                     break
%o A058903             else:
%o A058903                 continue
%o A058903             break
%o A058903 A058903_list = list(islice(A058903_gen(),20)) # _Chai Wah Wu_, May 10 2023
%Y A058903 Cf. A003635, A052491, A058898-A058907.
%K A058903 nonn,base
%O A058903 1,1
%A A058903 _N. J. A. Sloane_, Jan 09 2001