This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
a(1)=3 since 3 in base 1 ('unary') is 111 and, interpreted in base 10, 111 is a number divisible by 3, whereas 2 in base 1 is 11 and, interpreted in base 10, 11 is not divisible by 2.
a(3)=7 since 7 in base 3 is 21 and, interpreted in base 10, 21 is divisible by 7, whereas 3, 4, 5, 6 in base 3 are, respectively, 10, 11, 12, 20 and, interpreted in base 10, these are numbers not divisible, respectively, by 3, 4, 5, 6.
Trivial solutions (i.e., m<n for n>1 and m=n for n=1) are not considered here.
m,M=2,11
while M%m>0:
m,M=m+1,10*M+1
print(1,m)
for n in range(2,10):
m,M,d=n,10,10-n
while M%m>0:
m=m+1
u,s=m,0
while u%n==0:
u,s=u//n,10*s+d
M=M+1+s
print(n,m)
# Dimiter Skordev, Sep 28 2020
273 is a term: 273_10 = 100010001_2; 100010001 = 273*366337. - _Jon E. Schoenfield_, Oct 25 2019
Select[Range[1, 10^6, 2], Mod[ FromDigits@ IntegerDigits[#, 2], #] == 0 &] (* Giovanni Resta, Jul 12 2016 *)
n = 7; a(7) = A007088(7) mod 7 = 111 mod 7 = 6.
a[n_] := Mod[FromDigits[IntegerDigits[n, 2]], n]; Array[a, 100] (* Amiram Eldar, Jun 27 2022 *)
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