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 A219278 #11 Aug 13 2018 09:10:49
%S A219278 2,13,20,21,33,74,87,88,94,104,105,127,172,182,185,188,215,224,233,
%T A219278 240,249,258,278,281,292,293,304,329,337,365,399,416,433,440,468,471,
%U A219278 489,502,509,529,540,573,576,583,608,612,615,622,630,631,639,685,689,707
%N A219278 Numbers n such that ChebyshevT[16,n] is prime.
%C A219278 ChebyshevT[16,x] is the 16th Chebyshev polynomial of the first kind evaluated at x.
%H A219278 Robert Israel, <a href="/A219278/b219278.txt">Table of n, a(n) for n = 1..10000</a>
%p A219278 P:= unapply(orthopoly[T](16,x),x):
%p A219278 select(isprime @ P, [$1..1000]); # _Robert Israel_, Aug 13 2018
%t A219278 lst={}; Do[If[PrimeQ[ChebyshevT [16, n]], AppendTo[lst, n]], {n, 10^3}]; lst
%t A219278 Select[Range[800],PrimeQ[ChebyshevT[16,#]]&] (* _Harvey P. Dale_, Jan 23 2016 *)
%o A219278 (PARI) is(n)=ispseudoprime(polchebyshev(16,1,n)) \\ _Charles R Greathouse IV_, May 22 2017
%Y A219278 Cf. A144131, A144132, A219276, A219277.
%K A219278 nonn
%O A219278 1,1
%A A219278 _Michel Lagneau_, Nov 17 2012