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A069524
Smallest multiple of n with digit sum = 5, or 0 if no such number exists, e.g. a(3k) = a(11k) = 0.
8
5, 14, 0, 32, 5, 0, 14, 32, 0, 50, 0, 0, 104, 14, 0, 32, 221, 0, 1121, 140, 0, 0, 23, 0, 50, 104, 0, 140, 203, 0, 2201, 32, 0, 2210, 140, 0, 0, 3002, 0, 320, 41, 0, 2021, 0, 0, 230, 2021, 0, 22001, 50, 0, 104, 212, 0, 0, 1400, 0, 2030, 1121, 0, 122, 22010, 0, 320, 1040
OFFSET
1,1
COMMENTS
a(3k)= a(11k) =a(37k)=0. - Ray Chandler, Jul 30 2003
LINKS
FORMULA
a(n) = n*A088394(n). - R. J. Mathar, Aug 06 2019
MAPLE
nextL:= proc(L)
local m, q, Lp;
for m from 1 do
if L[m] > 0 then
if m = LinearAlgebra:-Dimension(L) then return <4, 0$(m-1), 1>
else Lp:= L;
Lp[1]:= L[m]-1;
Lp[2..m]:= 0;
Lp[m+1]:= L[m+1]+1;
return Lp;
fi
fi
od;
end proc:
N:= 300:
Agenda:= remove(t -> ormap(s -> (t mod s = 0), [3, 11, 37, 101, 137, 239]), {$1..N}):
L:= <5>: x:= 5:
A:= Vector(N):
while Agenda <> {} and x < 10^40 do
x:= add(L[i]*10^(i-1), i=1..LinearAlgebra:-Dimension(L));
found, Agenda:= selectremove(t -> x mod t = 0, Agenda);
if found <> {} then
A[convert(found, list)]:= x;
fi;
L:= nextL(L);
od:
convert(A, list): # Robert Israel, Sep 05 2019
MATHEMATICA
Table[If[MemberQ[Table[Mod[n, q], {q, {3, 11, 37, 101, 137, 239}}], 0], 0, With[{k=5000}, SelectFirst[n*Range[k], Total[IntegerDigits[#]] == 5&]]], {n, 70}] (* Harvey P. Dale, Nov 03 2024 *)
CROSSREFS
KEYWORD
base,nonn,changed
AUTHOR
Amarnath Murthy, Apr 01 2002
EXTENSIONS
More terms from Ray Chandler, Jul 30 2003
STATUS
approved