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A324582 a(n) = A002182(n) * A324581(n) = A002182(n) * A276086(A002182(n)).

%I A324582 #19 Mar 29 2019 19:08:00
%S A324582 2,6,36,30,300,15000,1260,42000,2940,288120,21176820,18480,66555720,
%T A324582 328703760,12298440,2232166860,360122920080,360360,103062960,
%U A324582 22107004920,4215068938080,129290917072196880,3525159950945805332160,90107494796113466546674800,645822919595173320,72532204477502449680,1648012277067163992784800
%N A324582 a(n) = A002182(n) * A324581(n) = A002182(n) * A276086(A002182(n)).
%C A324582 Note that gcd(A002182(n), A324581(n)) = A324198(A002182(n)) = 1 for all n because each term of A002182 is a product of primorial numbers (A002110).
%C A324582 See also comments in A324382.
%H A324582 Antti Karttunen, <a href="/A324582/b324582.txt">Table of n, a(n) for n = 1..512</a>
%H A324582 Michael De Vlieger, <a href="/A324582/a324582.png">Small chart of first terms</a>.
%H A324582 Michael De Vlieger, <a href="/A324582/a324582_1.png">2400 x 3600 chart of first terms</a>.
%H A324582 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A324582 <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%F A324582 a(n) = A002182(n) * A324581(n) = A002182(n) * A276086(A002182(n)).
%F A324582 a(n) = A324580(A002182(n)).
%t A324582 Block[{b = MixedRadix[Reverse@ Prime@ Range@ 20], s = DivisorSigma[0, Range[10^5]], t}, t = Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]; Array[#1 (Times @@ Power @@@ Transpose@ {Prime@ Range@ Length@ #2, Reverse@ #2}) & @@ {#, IntegerDigits[#, b]} &@ t[[#]] &, Length@ t]] (* _Michael De Vlieger_, Mar 18 2019 *)
%o A324582 (PARI)
%o A324582 \\ A002182 assumed to be precomputed
%o A324582 A276086(n) = { my(i=0,m=1,pr=1,nextpr); while((n>0),i=i+1; nextpr = prime(i)*pr; if((n%nextpr),m*=(prime(i)^((n%nextpr)/pr));n-=(n%nextpr));pr=nextpr); m; };
%o A324582 A324582(n) = A002182(n)*A276086(A002182(n));
%Y A324582 Subsequence of A324577.
%Y A324582 Cf. A002110, A002182, A276086, A324198, A324382, A324580, A324581.
%K A324582 nonn
%O A324582 1,1
%A A324582 _Antti Karttunen_, Mar 09 2019