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 A176680 #14 Sep 08 2022 08:45:53
%S A176680 5,29,509,536870909,
%T A176680 13164036458569648337239753460458804039861886925068638906788872189,
%U A176680 3369993333393829974333376885877453834204643052817571560137951281149,13803492693581127574869511724554050904902217944340773110325048447598589
%N A176680 Primes p == 2 (mod 3) of the form 2^n-3.
%C A176680 Also primes of the form 2^(2k+1)-3, since 2^n-3 == 2 (mod 3) iff n is odd. - _Robert Israel_, Feb 17 2016
%H A176680 Robert Israel, <a href="/A176680/b176680.txt">Table of n, a(n) for n = 1..11</a>
%p A176680 map(t -> 2^t-3, select(t -> isprime(2^t-3), [seq(t,t=1..2000, 2)])); # _Robert Israel_, Feb 17 2016
%t A176680 Flatten[Table[If[IntegerQ[Rationalize[N[ (1 + 2^n)/ 3]]] && PrimeQ[2^n - 3], 2^n - 3, {}], {n, 2, 100000}]]
%o A176680 (Magma) [2^n-3: n in [1..300] | IsPrime(2^n-3) and (2^n-3) mod 3 eq 2] - _Jaroslav Krizek_, Feb 17 2016
%Y A176680 Cf. A050414.
%K A176680 nonn
%O A176680 1,1
%A A176680 _Roger L. Bagula_, Apr 23 2010
%E A176680 Definition corrected by _Jaroslav Krizek_, Feb 17 2016
%E A176680 a(5)-a(7) from _Jaroslav Krizek_, Feb 17 2016