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%I #16 Jan 19 2019 03:39:31
%S 945,1575,2205,3465,5775,7425,8085,12705,15015,28215,47025,49875,
%T 69825,78975,81081,103455,131625,153153,182325,189189,297297,342225,
%U 351351,363375,387345,392445,474045,532875,570375,692835,742203,793611,1102725,1380825,1468935,1612875
%N Least odd primitive abundant number having its prime signature.
%C Ordering of exponents matters; 1575 and 2205 have unordered prime signatures (2, 2, 1) and (2, 1, 2) respectively.
%e 1575 = 3^2 * 5^2 * 7 has prime signature (2, 2, 1) and is an odd primitive abundant number (A006038). Since 1575 is the smallest such number, it is in the sequence. - _Michael B. Porter_, Nov 24 2018
%t lsig={}; lpab = {}; seq={}; Do[ d=Divisors[n]; If[Total[d] > 2 n && Intersection[ lpab, d] == {},AppendTo[lpab, n]; sig=FactorInteger[n][[;;,2]]; If[!MemberQ[ lsig,sig], AppendTo[seq, n]; AppendTo[lsig,sig]]],{n,3,1700000,2}]; seq (* _Amiram Eldar_, Dec 09 2018 *)
%Y Cf. A006038, A091191.
%K nonn
%O 1,1
%A _David A. Corneth_, Aug 18 2018
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