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A069528
Smallest multiple of n with digit sum = 9, or 0 if no such number exists (e.g., a(11k) = 0).
5
9, 18, 9, 36, 45, 18, 63, 72, 9, 90, 0, 36, 117, 126, 45, 144, 153, 18, 171, 180, 63, 0, 207, 72, 225, 234, 27, 252, 261, 90, 1116, 1152, 0, 306, 315, 36, 333, 342, 117, 360, 1107, 126, 1161, 0, 45, 414, 423, 144, 441, 450, 153, 1404, 1431, 54, 0, 504, 171, 522
OFFSET
1,1
COMMENTS
a(n) = 0 if n is a multiple of 11, 101, 271, 999 or 4649. - Robert Israel, Feb 14 2024
LINKS
MAPLE
unfinished:= true: V:= Vector(1000): V0:= select(t -> igcd(t, 11*101*271*4649) = 1 and t mod 999 <> 0, {$1..1000}):
for i1 from 0 while unfinished do
for i2 from 0 to i1 while unfinished do
for i3 from 0 to i2 while unfinished do
for i4 from 0 to i3 while unfinished do
for i5 from 0 to i4 while unfinished do
for i6 from 0 to i5 while unfinished do
for i7 from 0 to i6 while unfinished do
for i8 from 0 to i7 while unfinished do
for i9 from 0 to i8 while unfinished do
v:= 10^i1 + 10^i2 + 10^i3 + 10^i4 + 10^i5 + 10^i6 + 10^i7 + 10^i8 + 10^i9;
dv:= numtheory:-divisors(v);
for s in V0 intersect dv do
V[s]:= v;
od;
V0:= V0 minus dv;
unfinished:= evalb(V0 <> {});
od od od od od od od od od:
convert(V, list); # Robert Israel, Feb 14 2024
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Apr 01 2002
EXTENSIONS
More terms from Sascha Kurz, Apr 08 2002
STATUS
approved