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Number of ordered factorizations of A025487(n) as A025487(j) * A025487(k).
4

%I #11 Jul 06 2019 19:08:13

%S 1,2,3,2,4,4,5,6,2,6,3,8,4,7,6,10,6,8,9,4,12,2,4,8,9,12,8,14,4,8,10,

%T 10,15,12,16,6,12,3,12,11,6,18,4,5,16,18,8,16,6,14,12,12,21,2,8,10,20,

%U 20,10,20,9,16,13,18,24

%N Number of ordered factorizations of A025487(n) as A025487(j) * A025487(k).

%C A025487(j) and A025487(k) need not be distinct.

%C Because multiplying two members of A025487 always produces a member of A025487, the value of this function for all nonmembers of A025487 is 0.

%H Amiram Eldar, <a href="/A182762/b182762.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A000005(A181815(n)).

%e 36 has three different ordered factorizations into two members of A025487 (36 = 1*36 = 6*6 = 36*1). Therefore, since 36 = A025487(11), a(11) = 3.

%Y Cf. A000005, A025487, A181815.

%K nonn

%O 1,2

%A _Matthew Vandermast_, Nov 30 2010