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.
a048385 0 = 0
a048385 n = read (show (a048385 n') ++ show (m ^ 2)) :: Integer
where (n', m) = divMod n 10
-- Reinhard Zumkeller, Jul 08 2014
m=1;
for u=0:200 digit=dec2base(u,10)-'0'; digitp=digit.^2;
sol(m)=str2num(strrep(num2str(digitp), ' ', ''));m=m+1;
end
sol % Marius A. Burtea, May 17 2019
[0] cat [StringToInteger(&cat[IntegerToString(h): h in Reverse([i^2: i in Intseq(n)])]): n in [1..55]]; // Bruno Berselli, Jul 31 2012
a:= n-> (s-> parse(cat(seq(parse(s[i])^2, i=1..length(s)))))(""||n):
seq(a(n), n=0..70); # Alois P. Heinz, Jul 04 2014
Table[FromDigits[Flatten[IntegerDigits/@(IntegerDigits[n]^2)]],{n,0,80}] (* Harvey P. Dale, May 06 2019 *)
a(n) = if (n, fromdigits(concat(apply(d -> my (d2=d^2); if (d2, digits(d2), [0]), digits(n)))), 0) \\ Rémy Sigrist, May 17 2019
def digits(n):
d=[]
while n>0:
d.append(n%10)
n=n//10
return d
def sqdig(n):
new=0
num=digits(n)
spacing=0
while num:
k=num.pop(0)
new+=(10**(spacing))*(k**2)
if k>3:
spacing+=1
spacing+=1
return new
# David Nacin, Aug 19 2012
2619 is a term because replacing each digit d by d^2, recursively three times, a prime number is obtained: 2619 -> 436181 (prime); 436181 -> 169361641 (prime); 169361641 -> 13681936136161 (prime). 3173 is a term because replacing each digit d by d^2, recursively three times, a prime number is obtained: 3173 -> 91499 (prime); 91499 -> 811168181 (prime); 811168181 -> 6411136641641 (prime).
A316604 = {}; Do[ a=FromDigits[Flatten[IntegerDigits /@ (IntegerDigits[n]^2)]]; b=FromDigits[Flatten[IntegerDigits /@ (IntegerDigits[a]^2)]]; c=FromDigits[Flatten[IntegerDigits /@ (IntegerDigits[b]^2)]]; If[PrimeQ[a] && PrimeQ[b] && PrimeQ[c], AppendTo[A316604,n]], {n,100000}]; A316604
replace_digits(n) = my(d=digits(n), s=""); for(k=1, #d, s=concat(s, d[k]^2)); eval(s) is(n) = my(x=n, i=0); while(1, x=replace_digits(x); if(!ispseudoprime(x), return(0), i++); if(i==3, return(1))) \\ Felix Fröhlich, Jul 08 2018
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