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 A329237 #8 Nov 09 2019 04:14:16
%S A329237 0,0,0,0,0,0,0,0,0,1,5,8,10,15,20,29,42,57,81,118,179,246,348,481,654,
%T A329237 893,1231,1642,2188,3003,4033,5367,7252,9681,12961,17460,23351,31224,
%U A329237 41623,55455,74124,99127,132426,176466,235792,314338,420106,562476,751769,1006184
%N A329237 The number of base-2 Euler-Jacobi pseudoprimes (A047713) less than 2^n.
%H A329237 Amiram Eldar, <a href="/A329237/b329237.txt">Table of n, a(n) for n = 1..64</a>
%H A329237 Jan Feitsma and William F. Galway, <a href="http://www.cecm.sfu.ca/Pseudoprimes/index-2-to-64.html">Tables of pseudoprimes and related data</a>.
%e A329237 Below 2^10 = 1024 there is only one Euler-Jacobi pseudoprime, 561. Therefore a(10) = 1.
%t A329237 ejpspQ[n_] := CompositeQ[n] && PowerMod[2, (n - 1)/2, n] == Mod[JacobiSymbol[2, n], n]; s = {}; c = 0; p = 2; n = 1; Do[If[ejpspQ[n], c++]; If[n > p, AppendTo[s, c]; p *= 2], {n, 1, 2^20 + 1, 2}]; s
%Y A329237 Cf. A047713, A055551, A108797, A208276.
%K A329237 nonn
%O A329237 1,11
%A A329237 _Amiram Eldar_, Nov 08 2019