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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.

A181807 Number of divisors of A181806(n) that are highly composite (A002182).

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%I A181807 #19 Feb 16 2025 08:33:13
%S A181807 1,2,3,5,6,7,8,10,11,14,19,20,21,22,23,24,25,28,31,32,33,35,38,39,41,
%T A181807 48,49,52,53,57,59,65,67,69,77,81,82,86,91,94,103,105,107,114,118,122,
%U A181807 125,131,132,135,141,142,144,145,154,157,160,163,166,171,175,180
%N A181807 Number of divisors of A181806(n) that are highly composite (A002182).
%C A181807 Also, length of row A181806(n) in triangles A181802 and A181803.
%H A181807 David A. Corneth, <a href="/A181807/b181807.txt">Table of n, a(n) for n = 1..153</a>
%H A181807 A. Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/highly.txt">List of the first 1200 highly composite numbers</a>
%H A181807 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HighlyCompositeNumber.html">Highly composite number</a>
%F A181807 a(n) = A181801(A181806(n)).
%e A181807 A181806(4) = 12 has exactly five divisors (namely, 1, 2, 4, 6 and 12) that are members of A002182.  Hence, a(4) = 5.
%Y A181807 Cf. A002182, A181801, A181802, A181803, A181806.
%K A181807 nonn
%O A181807 1,2
%A A181807 _Matthew Vandermast_, Nov 27 2010
%E A181807 More terms from _Amiram Eldar_, Aug 29 2019 (calculated from the b-file at A181806)