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 A132195 #19 Apr 22 2025 08:03:31
%S A132195 1,7,12,23,47,84,172,335,590,1000,1858,3284,6083,10816,19539,35586,
%T A132195 65309,120625,224763,420658,790885,1494738
%N A132195 Number of three-prime Carmichael numbers less than 10^n.
%C A132195 a(n) = C_3(n) in Table 1, p. 34 of Chick (2007-2008) = card{c such that c is in A002997 INTERSECTION A014612 and c <= 10^n}.
%D A132195 Paulo Ribenboim, The Little Book of Bigger Primes, Springer-Verlag NY 2004. See p. 220.
%H A132195 J. M. Chick, <a href="https://arxiv.org/abs/0711.2915">Carmichael number variable relations: three-prime Carmichael numbers up to 10^24</a>, arXiv:0711.2915 [math.NT], 2007-2008, Table 1, p. 34.
%H A132195 Andrew Granville and Carl Pomerance, <a href="https://doi.org/10.1090/S0025-5718-01-01355-2">Two contradictory conjectures concerning Carmichael numbers</a>, Mathematics of Computation, Vol. 71, No. 238 (2002), pp. 883-908.
%Y A132195 For k-prime Carmichael numbers up to 10^n for k = 3,4,...,11, see A132195, A174612, A174613, A174614, A174615, A174616, A174617, A299710, A299711.
%Y A132195 Cf. A002997, A006931, A055553.
%K A132195 nonn,more
%O A132195 3,2
%A A132195 _Jonathan Vos Post_, Nov 19 2007