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A324581
a(n) = A276086(A002182(n)).
4
2, 3, 9, 5, 25, 625, 35, 875, 49, 2401, 117649, 77, 184877, 456533, 14641, 1771561, 214358881, 143, 20449, 2924207, 418161601, 8550986578849, 174859124550883201, 3575694237941010577249, 23298085122481, 1599034490244763, 32698656291015158587, 30466726698629, 39841104144361, 52099905419549, 89093921102069, 152355876914189, 260537564663909
OFFSET
1,1
COMMENTS
Note that gcd(a(n), A002182(n)) = A324198(A002182(n)) = 1 for all n because each term of A002182 is a product of primorial numbers (A002110).
FORMULA
a(n) = A276086(A002182(n)).
a(n) = A324582(n)/A002182(n).
A001221(a(n)) = A324381(n).
A001222(a(n)) = A324382(n).
MATHEMATICA
Block[{b = MixedRadix[Reverse@ Prime@ Range@ 20], s = DivisorSigma[0, Range[10^5]], t}, t = Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]; Array[Times @@ Power @@@ # &@ Transpose@ {Prime@ Range@ Length@ #, Reverse@ #} &@ IntegerDigits[(*a002182[[#]]*)t[[#]], b] &, Length@ t]] (* Michael De Vlieger, Mar 18 2019 *)
PROG
(PARI)
\\ A002182 assumed to be precomputed
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; };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 09 2019
STATUS
approved