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 A030481 #13 Jan 04 2024 01:41:55
%S A030481 4,9,25,49,289,841,2209,2809,4489,6241,6889,22201,22801,24649,66049,
%T A030481 80089,208849,426409,466489,822649,2042041,2468041,2866249,2886601,
%U A030481 4068289,6046681,6086089,6466849,6806881,6848689,8082649,8288641,8462281,8826841,22648081,26020201,26822041,28440889,44262409
%N A030481 Squares of primes, with property that all even digits occur together and all odd digits occur together.
%C A030481 Since the 10's digit of any odd square is even, all digits except the last must be even. - _Robert Israel_, Jan 04 2024
%H A030481 Robert Israel, <a href="/A030481/b030481.txt">Table of n, a(n) for n = 1..3000</a>
%p A030481 filter:= proc(n) local L;
%p A030481 convert(convert(floor(n/10),base,10),set) mod 2 = {0}
%p A030481 end proc:
%p A030481 [4, 9, op(select(filter, [seq(ithprime(i)^2, i=3..20000)]))]; # _Robert Israel_, Jan 04 2024
%Y A030481 Includes (2*10^(2k) + 2*10^k + 1)^2 for k in A296444.
%K A030481 nonn,base
%O A030481 1,1
%A A030481 _Patrick De Geest_
%E A030481 More terms from _Robert Israel_, Jan 04 2024