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%I #7 Oct 07 2016 09:54:42
%S 1,2,9,27,74,168,363,703,1297,2247,3742,5967,9241,13859,20307,29052,
%T 40786,56187,76233,101858,134377,175068,225640,287772,363673,455482,
%U 565977,697875,854594,1039500,1256787,1510547,1805833,2147607,2541870,2994543,3512737
%N Number of factorizations of m^n into exactly four factors, where m is a product of two distinct primes.
%H Alois P. Heinz, <a href="/A277240/b277240.txt">Table of n, a(n) for n = 0..10000</a>
%H <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (2,1,-2,-2,-2,5,2,0,-2,-5,2,2,2,-1,-2,1)
%F G.f.: -(x^12 +4*x^10 +9*x^9 +17*x^8 +17*x^7 +24*x^6 +17*x^5 +17*x^4 +9*x^3 +4*x^2 +1) / ((x^2+1) *(x^2+x+1)^2 *(x+1)^3 *(x-1)^7).
%e a(2) = 9: (2*3)^2 = 2*2*3*3 = 1*3*3*4 = 1*2*3*6 = 1*2*2*9 = 1*1*4*9 = 1*1*6*6 = 1*1*2*18 = 1*1*3*12 = 1*1*1*36.
%Y Column k=4 of A277239.
%K nonn
%O 0,2
%A _Alois P. Heinz_, Oct 06 2016
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