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A132378
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Smallest integer that starts with n and is divisible by every nonzero digit of n.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 132, 140, 15, 162, 175, 184, 198, 20, 210, 22, 234, 24, 250, 264, 2702, 280, 2916, 30, 312, 324, 33, 348, 3510, 36, 378, 384, 396, 40, 412, 420, 432, 44, 4500, 468, 476, 48, 4932, 50, 510, 520, 5310, 540, 55, 5610, 5705, 5800, 5940
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OFFSET
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1,2
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COMMENTS
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Note that a number that starts with n and is divisible by lcm(1, 2, ..., 9) = 2520 always satisfies the conditions. And there is such a number between n0000 and n2519. Therefore a(n) < 10000n + 2520. Hence to find a(n) one needs to check numbers n, n0..n9, n00..n99, n000..n999, n0000..n2519.
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LINKS
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MAPLE
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f:= proc(n) local r, d, q ;
r:= ilcm(op(convert(convert(n, base, 10), set) minus {0, 1}));
if n mod r = 0 then return n fi;
for d from 1 do
q:= -(n*10^d) mod r;
if q < 10^d then return n*10^d+q fi;
od
end proc:
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PROG
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lcm = lcm(all nonzero digits of n) for (p10 = 1;; p10 *= 10) { for (suffix = 0; suffix < p10; suffix++) { m = n * p10 + suffix; if (m % lcm == 0) return m; } }
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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Mikhail Dvorkin (mikhail.dvorkin(AT)gmail.com), Nov 10 2007
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STATUS
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approved
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