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A185166 Number of prime divisors of n (counted with multiplicity) of numbers k such that sum of proper divisors of k exceeds that of all smaller numbers. 1

%I #19 Aug 30 2019 04:18:39

%S 0,1,2,2,3,2,3,3,3,4,3,4,5,4,5,4,4,6,5,5,6,5,5,6,6,7,5,6,6,5,7,6,6,6,

%T 5,7,6,8,7,7,7,6,8,6,7,6,6,8,6,8,7,9,7,8,8,8,7,7,7,9,6,7,8,7,7,7,9,9,

%U 8,8,7,9,7,8,8,8,7,9,7,9,8,8,10,8,9,9,9

%N Number of prime divisors of n (counted with multiplicity) of numbers k such that sum of proper divisors of k exceeds that of all smaller numbers.

%H Amiram Eldar, <a href="/A185166/b185166.txt">Table of n, a(n) for n = 1..1000</a> (calculated from the b-file at A034090)

%F a(n) = A001222(A034090(n)).

%e a(1) = 0 because 1 = A034090(1) has no prime factors.

%e a(2) = 1 because 2 = A034090(2) has one prime factor, itself.

%e a(3) = 2 because 4 = A034090(3) = 2^2 has two prime factors (with multiplicity).

%Y Cf. A001222, A034090, A001065, A034091, A034287, A034288.

%K nonn

%O 1,3

%A _Jonathan Vos Post_, Feb 19 2011

%E More terms from _Amiram Eldar_, Aug 30 2019

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Last modified May 2 23:14 EDT 2024. Contains 372203 sequences. (Running on oeis4.)