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 A369109 #11 Jun 03 2024 03:48:15
%S A369109 1,4,19,105,604,4046,29482,220419,1712731,13706592,112196635,935286453
%N A369109 a(n) is the number of pairs of twin primes p and p+2 both less than or equal to 10^n such that p is congruent to 1 modulo 4.
%H A369109 Gareth A. Jones and Alexander K. Zvonkin, <a href="https://arxiv.org/abs/2401.00270">A number-theoretic problem concerning pseudo-real Riemann surfaces</a>, arXiv:2401.00270 [math.NT], 2023. See Table 4 at page 13.
%t A369109 a[n_] := Length[Select[Range[10^n-2], PrimeQ[#] && PrimeQ[#+2] && Mod[#,4] == 1 &]]; Array[a,10]
%o A369109 (PARI) lista(nmax) = {my(prev = 2, c = 0, pow = 10, n = 1, nm = nmax + 1); forprime(p = 3, , if(p > pow, print1(c, ", "); pow *= 10; n++; if(n == nm, break)); if(prev % 4 == 1 && p == prev + 2, c++); prev = p);} \\ _Amiram Eldar_, Jun 03 2024
%Y A369109 Cf. A001097, A001359, A004613, A006512, A007508, A369105, A369107, A369108, A369111.
%K A369109 nonn,more
%O A369109 1,2
%A A369109 _Stefano Spezia_, Jan 13 2024
%E A369109 a(11)-a(12) from _Amiram Eldar_, Jun 03 2024