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 A201558 #18 Apr 01 2015 17:31:48 %S A201558 0,0,0,0,0,0,0,0,0,0,2,4,2,1,1,2,4,1,2,3,7,7,7,1,4,7 %N A201558 Number of GA1 numbers A197638 with n >= 3 prime factors counted with multiplicity. %C A201558 The number of GA1 numbers with one (resp., two) prime factors is zero (resp., infinity). %C A201558 GA1 numbers with at least three prime factors are called "proper" - see A201557. %C A201558 For a(n), see Section 6.2 of "On SA, CA, and GA numbers", and below "kmax" in "Table of proper GA1 numbers up to 10^60". %H A201558 G. Caveney, J.-L. Nicolas, and J. Sondow, <a href="http://www.integers-ejcnt.org/l33/l33.pdf">Robin's theorem, primes, and a new elementary reformulation of the Riemann Hypothesis</a>, Integers 11 (2011), article A33. %H A201558 G. Caveney, J.-L. Nicolas and J. Sondow, <a href="http://arxiv.org/abs/1112.6010">On SA, CA, and GA numbers</a>, Ramanujan J., 29 (2012), 359-384 and arXiv:1112.6010. %H A201558 J.-L. Nicolas, <a href="http://math.univ-lyon1.fr/~nicolas/GAnumbers.html">Computation of GA1 numbers</a>, 2011. %H A201558 J.-L. Nicolas, <a href="http://math.univ-lyon1.fr/~nicolas/GA160">Table of proper GA1 numbers up to 10^60</a>, 2011. %e A201558 183783600 = 2^4 * 3^3 * 5^2 * 7 * 11 * 13 * 17 is the first of the a(13) = 2 GA1 numbers with 4 + 3 + 2 + 1 + 1 + 1 + 1 = 13 prime factors. %p A201558 See "Computation of GA1 numbers". %Y A201558 Cf. A067698, A197638, A197639, A201557. %K A201558 nonn %O A201558 3,11 %A A201558 Geoffrey Caveney, Jean-Louis Nicolas, and _Jonathan Sondow_, Dec 03 2011