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.
311314139^2 = 969164(931413113)21.
735^3 = 39706(537)5.
Select[Range[660000],SequenceCount[IntegerDigits[IntegerReverse[#^3]],IntegerDigits[#]]>0&] (* Harvey P. Dale, May 13 2025 *)
31471711^3 = 3(11717413)21891966598431.
The square root of 729 is 27. 27's digital reverse is 72. 72 appears in 729.
fQ[n_] := StringPosition[ IntegerString[n^2], StringReverse@ IntegerString@ n] != {}; k = 1; lst = {}; While[k < 3879404, If[ fQ@k, AppendTo[lst, k^2]]; k++ ]; lst (* Robert G. Wilson v, Jul 28 2010 *)
drsrQ[n_]:=Module[{s=Sqrt[n]},MemberQ[Partition[Reverse[ IntegerDigits[ n]], IntegerLength[ s],1], IntegerDigits[s]]]; Select[Range[ 28*10^5]^2, drsrQ] (* Harvey P. Dale, Dec 15 2015 *)
6317056^2 = 39905196507136 which ends with 6507136, so 6317056 is a term.
Select[Range[10^7], Function[k, Take[IntegerDigits[#^2], -Length@ k] == Reverse@ k]@ IntegerDigits@ # &] (* Michael De Vlieger, Mar 04 2016 *)
isA269588(n)=dn = digits(n); rn = subst(Polrev(dn), x, 10); nbd = #dn; (n^2 - rn) % 10^nbd == 0; \\ Michel Marcus, Mar 01 2016
\\ printA269588len(d) prints all terms of the sequence with d digits rev(n) = eval(concat(Vecrev(Str(n)))); { printA269588len(d) = my(l, u, n); l=ceil(d/2); u=floor(d/2); for(y=0, 10^l-1, n=rev(y^2 % 10^u)*10^l+y; if(#Str(n)==d && Mod(n, 10^d)^2==rev(n), print(n)); ); } \\ Max Alekseyev, Mar 07 2016
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