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 A048388 #17 Oct 14 2019 05:04:28 %S A048388 11,13,17,19,21,27,51,57,71,73,81,87,89,91,101,103,107,119,123,129, %T A048388 131,133,137,149,153,161,167,169,173,189,191,197,199,201,203,207,213, %U A048388 223,229,231,233,249,253,267,283,307,311,313,319,321,331,337,341,359,371 %N A048388 Replacing digits d in decimal expansion of n with d^2 yields a prime. %H A048388 Harvey P. Dale, <a href="/A048388/b048388.txt">Table of n, a(n) for n = 1..1001</a> [offset shifted by _Georg Fischer_, Oct 14 2019] %e A048388 199 = (1)(9)(9) -> (1)(81)(81) = 18181 which is a prime. %t A048388 Select[Range[400],PrimeQ[FromDigits[Flatten[IntegerDigits/@ (IntegerDigits[ #]^2)]]]&] (* _Harvey P. Dale_, Oct 13 2013 *) %Y A048388 Cf. A048385, A048389. %K A048388 nonn,base %O A048388 1,1 %A A048388 _Patrick De Geest_, Mar 15 1999