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 A381969 #12 Mar 30 2025 09:52:58 %S A381969 3701,65442077,8410957371097 %N A381969 Primes p with the property that PreviousPrime(p) is a substring of p^2. %C A381969 a(4) <= 39835421121719177570419. %C A381969 p = 1410901659681109388941762308365764228483 is also a member of this sequence and it is the only known term that is the greater of a twin prime pair. %H A381969 Carlos Rivera, <a href="https://www.primepuzzles.net/coll20th/coll20th-017.htm">Coll.20th-017. The square of Prime contains Prevprime</a>, The Prime Puzzles and Problems Connection. %e A381969 3701 is a term because PreviousPrime(3701) = 3697 is a substring of 3701^2 = 13697401. %t A381969 Select[Prime@Range[10^4],StringContainsQ[ToString[#^2],ToString[NextPrime[#,-1]]]&] %Y A381969 Cf. A052073. %K A381969 nonn,base,bref,more %O A381969 1,1 %A A381969 _Giorgos Kalogeropoulos_, Mar 11 2025