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%I #12 Oct 11 2017 21:58:15
%S 1,3,9,15,36,45,126,96,144,120,324,240,336,432,360,480,672,864,720,
%T 840,1260,1008,1080,1920,1440,2040,1680,2016,2160,3024,2880,2520,4620,
%U 4200,3360,5544,4320,6048,6300,9072,7200,11700,5040,12096,7920,7560,10800
%N a(n) = the smallest positive integer with exactly n positive "isolated divisors". A divisor, k, of n is isolated if neither (k-1) nor (k+1) divides n.
%H Ray Chandler, <a href="/A133997/b133997.txt">Table of n, a(n) for n=1..577</a>
%t With[{s = KeySort@ PositionIndex@ Table[1 + Count[Rest@ Divisors@ n, _?(NoneTrue[# + {-1, 1}, Divisible[n, #] &] &)], {n, 12000}]}, Function[t, TakeWhile[#, # > 0 &] &@ ReplacePart[t, Map[# -> Lookup[s, #][[1]] &, Keys@ s]]]@ ConstantArray[0, Last@ Keys@ s]] (* _Michael De Vlieger_, Oct 11 2017 *)
%Y Cf. A133996, A132881.
%K nonn
%O 1,2
%A _Leroy Quet_, Oct 01 2007
%E Extended by _Ray Chandler_, Jun 24 2008
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