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 A226217 #25 Sep 02 2023 18:32:52
%S A226217 11,13,17,19,41,43,47,97,101,103,107,109,113,127,131,137,139,149,151,
%T A226217 157,163,167,173,179,181,191,193,197,199,401,409,419,421,431,433,439,
%U A226217 443,449,457,461,463,467,479,487,491,499,907,911,919,929,937,941,947,953
%N A226217 Primes whose first digit is a square.
%H A226217 K. D. Bajpai, <a href="/A226217/b226217.txt">Table of n, a(n) for n = 1..10000</a>
%e A226217 97 is a prime whose first digit is 9, which is 3^2, so 97 is a term.
%p A226217 KD := proc() local a,b,d,e; a:= ithprime(n); b:=length(a); d:=a/(10^(b-1)); e:=floor(d); if evalf(sqrt(e))=floor(evalf(sqrt(e))) then RETURN (a):fi;end:seq(KD(),n=1..200);
%t A226217 Select[Prime[Range[200]],MemberQ[{1,4,9},First[IntegerDigits[#]]]&] (* _Harvey P. Dale_, Sep 02 2023 *)
%o A226217 (Python)
%o A226217 from sympy import primerange
%o A226217 from itertools import count, islice
%o A226217 def agen(): yield from (p for e in count(1) for k in [1, 4, 9] for p in primerange(k*10**e, (k+1)*10**e))
%o A226217 print(list(islice(agen(), 54))) # _Michael S. Branicky_, Jun 25 2022
%Y A226217 Cf. A223458 (similar sequence for primes: first digit a composite number).
%K A226217 nonn,base
%O A226217 1,1
%A A226217 _K. D. Bajpai_, Aug 24 2013