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%I #10 Apr 01 2020 14:00:48
%S 1,2,3,8,10,12,14,32,54,60,66,72,78,84,90,256,272,288,304,320,336,352,
%T 368,384,500,520,810,840,870,900,930,1920,1980,2040,2100,2592,2664,
%U 2736,2808,2880,2952,3024,3096,3168,3240,3312,3384,3456,4116,4200,4284,4368,4452,4536,4620,4704,4788,4872,4956,5040,5124,5208,5292,16384,16640,16896,17152,17408,17664,17920,18176,18432,18688,18944,19200,19456,19712,19968,20224,20480
%N a(n) = Product_{k>=1} floor(n^(1/k)).
%C Although written as an infinite product, all but finitely many terms in the product are 1.
%F a(n) < n^log(n) for n > 4.
%e a(8) = 8 * floor(sqrt(8)) * floor(8^(1/3)) * 1 * ... = 8 * 2 * 2 * 1 * ... = 32.
%o (PARI) a(n)=prod(k=1,floor(log(n+1/2)/log(2)),floor(sqrtn(n+1/2,k)))
%Y Cf. A190650, A006218, A061567.
%K nonn
%O 1,2
%A _Franklin T. Adams-Watters_, May 16 2011
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