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%I #15 Oct 03 2021 19:27:23
%S 1,1,1,3,1,5,1,8,3,5,1,23,1,5,5,23,1,23,1,23,5,5,1,91,3,5,8,23,1,52,1,
%T 60,5,5,5,143,1,5,5,91,1,52,1,23,23,5,1,328,3,23,5,23,1,91,5,91,5,5,1,
%U 339,1,5,23,161,5,52,1,23,5,52,1,686,1,5,23,23,5,52,1,328,23,5,1,339,5
%N Number of factorizations of (n,n) into pairs (j,k).
%C Pairs (j,k) must satisfy j>1, k>=1; (a,b)*(x,y)=(a*x,b*y); unit is (1,1).
%C a(n) depends only on prime signature of n (cf. A025487). So a(24) = a(375) since 24=2^3*3 and 375=3*5^3 both have prime signature (3,1).
%H Giovanni Resta, <a href="/A051707/b051707.txt">Table of n, a(n) for n = 1..1000</a>
%e (6,6)=(2,1)*(3,6)=(2,6)*(3,1)=(2,2)*(3,3)=(2,3)*(3,2), so a(6)=5.
%Y Cf. A050354, A108461, A108455, A348161 (into at most two pairs).
%Y a(A025487) = A108460.
%Y a(p^k) = A108457(k).
%Y a(A002110) = A108459.
%Y Main diagonal of A108455.
%K nonn,nice,easy
%O 1,4
%A _Yasutoshi Kohmoto_
%E Edited by _Christian G. Bower_, Jun 03 2005
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