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.
N:= 1000: # for terms before the first term > N
V:= Vector(N):
A[1]:= 5: V[5]:= 1:
for n from 2 do
S:= {seq(seq(k*p,k=1..N/p),p=numtheory:-factorset(A[n-1]))};
for s in sort(convert(S,list)) do
if V[s] = 0 then
A[n]:= s;
break
fi
od;
if V[s] = 1 then break fi;
V[s]:= 1;
od:
seq(A[i],i=1..n-1); # Robert Israel, Jan 18 2016
f[s_List] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]]; Nest[f, {6, 2}, 71] (* Michael De Vlieger, Jan 21 2016, after Robert G. Wilson v at A064413 *)
from math import gcd
def aupton(terms):
alst, aset = [1, 6], {1, 6}
for n in range(2, terms+1):
k = 2
while True:
while k in aset: k += 1
if gcd(alst[-1], k) != 1: alst.append(k); aset.add(k); break
k += 1
return alst[1:]
print(aupton(73)) # Michael S. Branicky, Jun 02 2021
from math import gcd
def aupton(terms):
alst, aset = [12], {12}
for n in range(2, terms+1):
k = 2
while True:
while k in aset: k += 1
if gcd(alst[-1], k) != 1:
alst.append(k); aset.add(k); break
k += 1
return alst
print(aupton(73)) # Michael S. Branicky, Dec 02 2021
from math import gcd
def aupton(terms):
alst, aset = [1, 10], {1, 10}
for n in range(2, terms+1):
k = 2
while True:
while k in aset: k += 1
if gcd(alst[-1], k) != 1: alst.append(k); aset.add(k); break
k += 1
return alst[1:]
print(aupton(73)) # Michael S. Branicky, Oct 02 2021
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