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(7) = 360 as the smallest positive integer k such that the concatenation a(1)a(2)..a(6)k is divisible by lcm(1..7) = 420. - _David A. Corneth_, Jul 21 2020
N:= 1: R:= 1: C:= 1:
for n from 2 to 60 do
N:= ilcm(N,n);
for d from 1 do
x:= -C*10^d mod N;
if x = 0 then lx:= 1 else lx:= 1+ilog10(x) fi;
if lx = d then
R:= R,x;
C:= C*10^d+x;
break
elif lx < d then
k:= ceil((10^(d-1)-x)/N);
x:= x + k*N;
if x < 10^d then
R:= R,x;
C:= C*10^d+x;
break
fi fi
od; od:
R; # Robert Israel, Sep 16 2020
a(n) = {if(n==1,return(1));for(n1 = 0, oo, ; k[n]=eval(concat(Str(k[n-1]), n1)); n2=0; for(n3 = 1, n, if(k[n] % n3 == 0, n2+=1; if(n2==n, return(k[n])))))};
k = vector(10000);print1(k[1]=1,", ");for(j=1, 20, print1(a(j+1) - a(j)*10^(length(Str(a(j+1))) - length(Str(a(j)))), ", "))
\\ See Corneth link. David A. Corneth, Jul 21 2020
a(4) = 1012 hence a(5)=10120 and a(6) = 101202.
a(n)={if(n==1,return(1));for(n1=0,oo,k=eval(concat(Str(a(n-1)),n1));n2=0;for(n3=1,n,if(k%n3==0,n2+=1;if(n2==n,return(k)))))};
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