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A069530 Smallest multiple of n with digit sum = 11, or 0 if no such number exists.

%I A069530 #19 Feb 15 2024 01:13:58
%S A069530 29,38,0,56,65,0,56,56,0,290,209,0,65,56,0,128,119,0,38,380,0,308,92,
%T A069530 0,425,182,0,56,29,0,155,128,0,272,245,0,74,38,0,560,164,0,344,308,0,
%U A069530 92,47,0,245,650,0,416,371,0,605,56,0,290,236,0,1037,434,0,128,65,0,335
%N A069530 Smallest multiple of n with digit sum = 11, or 0 if no such number exists.
%C A069530 a(n) = 0 if n is divisible by 3, 1111, 1507, 2849, 3367, 4849, 5291 or 7373. - _Robert Israel_, Feb 14 2024
%H A069530 Robert Israel, <a href="/A069530/b069530.txt">Table of n, a(n) for n = 1..10000</a>
%F A069530 a(3k) = 0 for k = 1, 2, 3, ....
%F A069530 a(n) = n*A088400(n). - _R. J. Mathar_, Aug 06 2019
%p A069530 A069530 := proc(n)
%p A069530     local m ;
%p A069530     if modp(n,3) = 0 then
%p A069530          0 ;
%p A069530     else
%p A069530         for m from 1 do
%p A069530             if digsum(m*n) = 11 then
%p A069530                 return m*n ;
%p A069530             end if;
%p A069530         end do:
%p A069530     end if;
%p A069530 end proc:
%p A069530 seq(A069530(n),n=1..70) ; # _R. J. Mathar_, Aug 06 2019
%o A069530 (PARI) sod(n) = {digs = digits(n); return (sum(i=1, #digs, digs[i]));}
%o A069530 a(n) = {if (n % 3 == 0, return (0)); k = 1; while (sod(k*n) != 11, k++); k;} \\ _Michel Marcus_, Sep 14 2013
%Y A069530 Cf. A166311, A069521, A069522, A069523, A069524, A069525, A069526, A069527, A069528, A069529.
%K A069530 base,nonn
%O A069530 1,1
%A A069530 _Amarnath Murthy_, Apr 01 2002
%E A069530 More terms from _Sascha Kurz_, Apr 08 2002