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A181807 Number of divisors of A181806(n) that are highly composite (A002182). 4

%I #18 Sep 19 2019 09:04:23

%S 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 48,49,52,53,57,59,65,67,69,77,81,82,86,91,94,103,105,107,114,118,122,

%U 125,131,132,135,141,142,144,145,154,157,160,163,166,171,175,180

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

%C Also, length of row A181806(n) in triangles A181802 and A181803.

%H David A. Corneth, <a href="/A181807/b181807.txt">Table of n, a(n) for n = 1..153</a>

%H A. Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/highly.txt">List of the first 1200 highly composite numbers</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HighlyCompositeNumber.html">Highly composite number</a>

%F a(n) = A181801(A181806(n)).

%e A181806(4) = 12 has exactly five divisors (namely, 1, 2, 4, 6 and 12) that are members of A002182. Hence, a(4) = 5.

%Y Cf. A002182, A181801, A181802, A181803, A181806.

%K nonn

%O 1,2

%A _Matthew Vandermast_, Nov 27 2010

%E More terms from _Amiram Eldar_, Aug 29 2019 (calculated from the b-file at A181806)

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Last modified April 24 02:46 EDT 2024. Contains 371917 sequences. (Running on oeis4.)