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 A187409 #7 Sep 20 2022 16:25:38
%S A187409 3,9,20,33,54,73,102,131,164,201,248,293,342,393,452,513,582,655,728,
%T A187409 801,884,971,1070,1153,1256,1353,1462,1571,1694,1807,1928,2055,2180,
%U A187409 2319,2454,2593,2742,2891,3044,3201,3374,3541,3710,3885,4052,4245,4422,4613
%N A187409 n^2 + nextprime(n^2).
%e A187409 1^2+2=3, 2^2+5=9, 3^2+11=20,..
%t A187409 Table[n2=n^2; NextPrime[n2]+n2, {n,100}]
%t A187409 #+NextPrime[#]&/@(Range[100]^2) (* _Harvey P. Dale_, Sep 20 2022 *)
%Y A187409 Cf. A053000, A056927, A007491.
%K A187409 nonn
%O A187409 1,1
%A A187409 _Vladimir Joseph Stephan Orlovsky_, Mar 09 2011