A113560
Least multiple of n in which the n-th digit from left is 5.
Original entry on oeis.org
5, 150, 105, 10052, 10005, 1000050, 1000055, 100000056, 100000035, 10000000050, 10000000065, 1000000000056, 1000000000025, 100000000000054, 100000000000005, 10000000000000256, 10000000000000135, 1000000000000000152, 1000000000000000075, 1000000000000000000500
Offset: 1
a(4) = 4 * 2513 = 10052, in which the fourth digit is 5.
-
f:= proc(n) local d,m,R,v;
for d from n do
R:= {};
for m from ceil(10^(d-1)/n) do
v:= m*n;
if v > 10^d then break fi;
v:= v mod 10^(d-n+1);
if member(v,R) then break fi;
if floor(v/10^(d-n)) = 5 then return m*n fi;
R:= R union {v};
od
od;
end proc:
map(f, [$1..30]); # Robert Israel, Mar 15 2024
A113561
Least multiple of n in which the n-th digit from left is 6.
Original entry on oeis.org
6, 16, 126, 1016, 100060, 100026, 1000006, 10000016, 100000026, 10000000060, 10000000076, 100000000056, 1000000000116, 10000000000046, 1000000000000065, 1000000000000016, 10000000000000016, 100000000000000026, 1000000000000000056
Offset: 1
a(4)= 10060, in which the fourth digit is 6.
A113562
Least multiple of n in which the n-th digit from left is 7.
Original entry on oeis.org
7, 170, 117, 10072, 100070, 1000074, 1000027, 100000072, 100000017, 10000000070, 10000000087, 1000000000176, 1000000000077, 100000000000278, 1000000000000170, 10000000000000176, 10000000000000067, 1000000000000000170
Offset: 1
a(4)= 10072, in which the fourth digit is 7.
-
lmn7[n_]:=Module[{k=Ceiling[10^(n-1)/n]},While[NumberDigit[k n,IntegerLength[ k n]-n]!=7,k++];k n]; Array[lmn7,10] (* The program generates the first 10 terms of the sequence. *) (* Harvey P. Dale, Nov 02 2022 *)
A113563
Least multiple of n in which the n-th digit from left is 8.
Original entry on oeis.org
8, 18, 108, 1008, 100080, 100008, 1000048, 10000008, 100000008, 10000000080, 10000000098, 100000000008, 1000000000038, 10000000000018, 1000000000000080, 1000000000000048, 10000000000000118, 100000000000000008, 1000000000000000018
Offset: 1
a(4)= 1008, in which the fourth digit is 8.
A113564
Least multiple of n in which the n-th digit from left is 9.
Original entry on oeis.org
9, 190, 129, 10092, 100090, 1000092, 1000069, 100000096, 100000089, 10000000090, 10000000109, 1000000000092, 1000000000129, 100000000000096, 1000000000000095, 10000000000000096, 10000000000000169
Offset: 1
a(4)= 10092, in which the fourth digit is 9.
More terms from Peter Soung (soung3(AT)hotmail.com), Jan 23 2006
Showing 1-5 of 5 results.