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 A086837 #16 Jun 29 2019 02:25:44
%S A086837 341,1387,2047,2701,31621,42799,49141,49981,60701,83333,88357,90751,
%T A086837 104653,129889,130561,150851,162193,164737,219781,226801,241001,
%U A086837 249841,282133,1194649,1678541,2035153,2134277,2163001,2284453,2304167,2491637
%N A086837 Brilliant Sarrus numbers.
%D A086837 J. Earls, Mathematical Bliss, Pleroma Publications, 2009, page 10. [From _Jason Earls_, Nov 21 2009]
%H A086837 Amiram Eldar, <a href="/A086837/b086837.txt">Table of n, a(n) for n = 1..10000</a>
%e A086837 2701 is a term because 2^2700 == 1 (mod 2701) and 2701 = 37*73.
%t A086837 brilQ[n_] := Block[{fi = FactorInteger@n}, Plus @@ Last /@ fi == 2 && Floor[ Log[10, fi[[1, 1]]]] == Floor[Log[10, fi[[-1, 1]]]]]; Select[Range[10^5], PowerMod[2, # - 1, #] == 1 && brilQ[#] &] (* _Amiram Eldar_, Jun 28 2019 after _Robert G. Wilson v_ at A078972 *)
%Y A086837 Intersection of A001567 and A078972.
%Y A086837 Cf. A084653.
%K A086837 base,nonn
%O A086837 1,1
%A A086837 _Jason Earls_, Aug 08 2003
%E A086837 More terms from _Jack Brennen_, Dec 21 2004