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%I #15 Nov 02 2024 12:31:41
%S 10,10,12,12,10,12,14,16,18,100,110,108,104,112,105,112,102,108,114,
%T 100,105,110,115,120,100,104,108,112,116,120,124,128,132,102,105,108,
%U 111,114,117,120,123,126,129,132,135,138,141,144,147,100,102,104,106,108
%N a(n) is the least multiple of n with more decimal digits than n.
%H Rémy Sigrist, <a href="/A377565/b377565.txt">Table of n, a(n) for n = 1..9999</a>
%F a(n) = n * A097327(n).
%e For n = 42: 42 and 2*42 have the same number of digits, while 3*42 has more digits, so a(42) = 3*42 = 126.
%t Table[n*Ceiling[10^IntegerLength[n]/n], {n, 120}] (* _Michael De Vlieger_, Nov 02 2024 *)
%o (PARI) a(n) = n * ceil(10^#digits(n) / n)
%o (Python)
%o def A377565(n): return n-1+10**(l:=len(str(n)))-(pow(10,l,n)-1)%n # _Chai Wah Wu_, Nov 02 2024
%Y Cf. A055642, A097327, A109940.
%K nonn,base,easy
%O 1,1
%A _Rémy Sigrist_, Nov 01 2024