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.
$MaxExtraPrecision = 2^10; a[n_] := a[n] = Block[{k = 10, m = a[n - 1]}, id = IntegerDigits@ m; lng = Length@ id; While[c = Ceiling[ Sqrt[ m*k]]^2; Take[ IntegerDigits@ c, lng] != id, k *= 100]; Min[c, (Sqrt[m]*10^(lng/2) + 1)^2]]; a[1] = 1; Array[a, 11] (* Robert G. Wilson v, Dec 18 2014 *)
a(n)=k=n;s=1;while(s<10^7,if(s%10,if(s^3\(10^(#Str(s^3)-#Str(k)))==k,print1(s^3,", ");k=s^3));s++) a(3)
def f(x):
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**3)
if S.startswith(str(n)):
print(s**3,end=', ')
n = s**3
s += 1
f(3)
a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++) a(3)
def f(x):
print(x, end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2, end=', ')
n = s**2
s += 1
f(3)
a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++) a(5)
def f(x):
print(x, end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2, end=', ')
n = s**2
s += 1
f(5)
R:= 6: x:= 6: s:= 2:
for iter from 1 while length(x) < 1000 do
for d from 1 do
if d::even then sp:= 1+ 10^(d/2)*s
else
sp:= ceil(sqrt(10^d*x));
if sp mod 10 = 0 then sp:=sp+1; fi
fi;
if sp^2 < (x+1)*10^d then
x:= sp^2; s:= sp; R:= R, x; break
fi
od;
od:
R; # Robert Israel, Nov 25 2020
a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++) a(7)
def f(x):
print(x, end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2, end=', ')
n = s**2
s += 1
f(7)
a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++) a(7)
def f(x):
print(x, end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2, end=', ')
n = s**2
s += 1
f(7)
a(n)=k=n;s=1;while(s<5*10^7,if(s%10,if(s^2\(10^(#Str(s^2)-#Str(k)))==k,print1(s^2,", ");k=s^2));s++) a(2)
def f(x):
print(x,end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2,end=', ')
n = s**2
s += 1
f(2)
from math import isqrt
def anext(an):
lo, hi = an*10, an*10 + 9
while True:
found = False
if isqrt(hi)**2 > lo: return (isqrt(lo)+1)**2
lo, hi = lo*10, hi*10 + 9
n, an = 1, 2
for n in range(2, 17):
an = anext(an)
print(n, an) # Michael S. Branicky, Feb 25 2021
a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++) a(8)
def f(x):
print(x, end=', ')
n = x
s = 1
while s < 10**7:
if s % 10:
S = str(s**2)
if S.startswith(str(n)):
print(s**2, end=', ')
n = s**2
s += 1
f(8)
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