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a(n) is the maximum number of prime signatures of numbers with n divisors that have the same number of prime divisors (counted with multiplicity).
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%I #13 Jun 22 2022 02:32:09

%S 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%T 1,2,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%U 1,1,1,3,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1

%N a(n) is the maximum number of prime signatures of numbers with n divisors that have the same number of prime divisors (counted with multiplicity).

%H Amiram Eldar, <a href="/A355032/b355032.txt">Table of n, a(n) for n = 1..10000</a>

%F a(A355033(n)) = n.

%e a(2) = 1 since the numbers with 2 divisors are all primes and thus have only 1 prime signature.

%e a(36) = 2 since numbers with 36 divisors have 2 prime signatures, p1^5 * p2^5 and p1 * p2 * p3^8, that correspond to numbers with 10 prime divisors (counted with multiplicity).

%e a(72) = 3 since numbers with 72 divisors have 3 prime signatures, p1 * p2^5 * p3^5, p1^2 * p2^2 * p3^7 and p1 * p2 * p3 * p4^8, that correspond to numbers with 11 prime divisors (counted with multiplicity).

%t Table[Max[Tally[Total[#-1]& /@ f[n]][[;;,2]]], {n, 1, 100}] (* using the function f by _T. D. Noe_ at A162247 *)

%Y Cf. A000005, A001222, A118914, A162247, A355028, A355030, A355031, A355033.

%K nonn

%O 1,36

%A _Amiram Eldar_, Jun 16 2022