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 A038370 #19 Aug 27 2025 18:03:05
%S A038370 101,113,149,191,1163,1259,1361,1493,2647,1811,11003,11213,11443,
%T A038370 11699,11969,12251,12569,12893,13241,13613,14009,14411,14843,15299,
%U A038370 15761,16253,16763,17291,27847,18413,19001,29611,210241,110899,311561,112253,112967
%N A038370 Smallest prime with "n^2" as central digit(s).
%C A038370 1195 is the smallest n such that 2 digits are needed on both sides of 1195^2 = 1428025 to give prime 10142802503. - _Michel Marcus_, Jun 05 2013
%o A038370 (PARI) a(n) = {a = 1; ok = 0; while (!ok, lena = #Str(a); lenn = #Str(n^2); for (b=0, 10^lena - 1, p = b + 10^lena*n^2 + 10^(lenn+lena)*a; if (isprime(p), return (p)););a++;);} \\ _Michel Marcus_, Jun 05 2013
%Y A038370 Cf. A084413, A069691.
%K A038370 easy,nonn,base,changed
%O A038370 0,1
%A A038370 _Zak Seidov_, Jun 25 2003
%E A038370 Corrected by _Robert G. Wilson v_, Jun 27 2003
%E A038370 a(19) corrected by _Sean A. Irvine_, Jan 12 2021