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.
%I A028866 #15 Feb 13 2020 01:16:46 %S A028866 4,9,25,49,169,289,1369,4489,6889,11449,27889,113569,134689,146689, %T A028866 344569,2778889,27777888889,111113555569,111133556689,111333666889, %U A028866 113344668889,444444888889,1111133355666889,1133444466888889 %N A028866 Squares of primes having digits in nondecreasing order. %C A028866 What is the rate of growth of this sequence? %t A028866 Select[Prime[Range[100]]^2, IntegerDigits[#] == Sort[IntegerDigits[#]] &] (* _Alonso del Arte_, Jan 18 2017 *) %o A028866 (PARI) is(n)=my(d=digits(n));d==vecsort(d) && issquare(n,&n) && isprime(n) \\ _Charles R Greathouse IV_, Jun 05 2013 %Y A028866 Subsequence of A052043. %Y A028866 Cf. A028865, A028868, A028869. %K A028866 nonn,base,less %O A028866 1,1 %A A028866 _Patrick De Geest_ %E A028866 Title changed to reflect terms by _Sean A. Irvine_, Feb 12 2020