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Primorial deflation of the n-th highly composite number: the unique integer k such that A108951(k) = A002182(n).
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%I #40 Jan 13 2020 18:19:50

%S 1,2,4,3,6,12,9,24,10,20,15,40,30,60,28,21,56,42,84,63,168,126,336,

%T 140,66,189,280,132,99,264,198,528,220,396,297,440,792,156,117,312,

%U 234,624,260,468,351,520,936,390,1040,1872,780,585,306,1560,340,612,459,680,1224,510,1360,2448,1020,765,342,2040,1530,684,513

%N Primorial deflation of the n-th highly composite number: the unique integer k such that A108951(k) = A002182(n).

%H Antti Karttunen, <a href="/A329902/b329902.txt">Table of n, a(n) for n = 1..10000</a> (computed from the b-file of A002182)

%H Michael De Vlieger, <a href="/A329902/a329902.txt.gz">List of a(n) for n = 1..779674</a> (gzipped text file, prepared from Flammenkamp's data)

%H Michael De Vlieger, <a href="/A329902/a329902_1.txt">List of a(n) for n = 1..500000</a> (noncompressed text file, an abridged version of above)

%F a(n) = A329900(A002182(n)) = A319626(A002182(n)).

%F a(n) = A181815(A306802(n)).

%F A108951(a(n)) = A002182(n). [Highly composite numbers (undeflated)]

%F A056239(a(n)) = A112778(n). [Number of prime factors, counted with multiplicity]

%F A001222(a(n)) = A112779(n). [Largest exponent in the prime factorization]

%F A329605(a(n)) = A002183(n). [Number of divisors]

%F A329040(a(n)) = A324381(n).

%F A324888(a(n)) = A324382(n).

%F a(A330748(n)) = A330743(n).

%t Map[Times @@ Prime@(TakeWhile[Reap[FixedPointList[Block[{k = 1}, While[Mod[#, Prime@ k] == 0, k++]; Sow[k - 1]; #/Product[Prime@ i, {i, k - 1}]] &, #]][[-1, 1]], # > 0 &]) &, Take[Import["https://oeis.org/b002182.txt", "Data"][[All, -1]], 69] ] (* _Michael De Vlieger_, Jan 13 2020, imports b-file at A002182 *)

%Y Cf. A002182, A002183, A056239, A108951, A112778, A112779, A306802, A319626, A324381, A324382, A324581, A324582, A324888, A329040, A329605, A329900, A330743, A330748.

%Y Subsequence of A181815.

%K nonn

%O 1,2

%A _Antti Karttunen_, Dec 22 2019

%E More linking formulas added by _Antti Karttunen_, Jan 13 2020