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 A107289 #8 Jan 09 2019 01:53:35
%S A107289 4,5,7,16,17,25,26,28,29,32,34,37,38,40,44,47,49,50,52,53,56,61,62,64,
%T A107289 65,70,73,79,82,83,89,91,98,106,107,109,115,116,118,119,125,127,133,
%U A107289 137,142,143,146,149,151,154,155,160,161,164,170,173,181,182,187,188,199
%N A107289 Numbers k such that the sum of digits of k^2 is a prime.
%F A107289 a(n) = sqrt(A065408(n)).
%t A107289 bb={};Do[If[PrimeQ[Apply[Plus, IntegerDigits[n^2]]], bb=Append[bb, n]], {n, 500}];bb
%o A107289 (PARI) isok(n) = isprime(sumdigits(n^2)); \\ _Michel Marcus_, Jan 09 2019
%Y A107289 Cf. A065408.
%K A107289 nonn,base
%O A107289 1,1
%A A107289 _Zak Seidov_, May 20 2005