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A330745 Primorial deflation of A019505(n), where A019505(n) is smallest number with same number of divisors as 2*A019505(n-1), starting from A019505(1) = 1. 2

%I

%S 1,2,4,3,6,12,24,10,20,40,30,60,21,42,84,168,336,66,132,264,528,396,

%T 792,117,234,468,936,1872,780,1560,612,1224,2448,1020,2040,684,1368,

%U 2736,1140,2280,4560,1596,3192,1380,2760,5520,1932,3864,7728,15456,11592,23184,1827,3654,7308,14616,29232,1953,3906,7812,15624,31248,62496

%N Primorial deflation of A019505(n), where A019505(n) is smallest number with same number of divisors as 2*A019505(n-1), starting from A019505(1) = 1.

%C a(n) is the unique integer k such that A108951(k) = A019505(n).

%C Conjectured to be a subsequence of A329902.

%C Terms computed from b-file of A019505 provided by _R. J. Mathar_.

%F a(n) = A329900(A019505(n)).

%o (PARI) A330745(n) = A329900(A019505(n));

%Y Cf. A019505, A108951, A329900, A329902.

%Y Cf. A330744 (conjectured subsequence).

%K nonn

%O 1,2

%A _Antti Karttunen_, Jan 10 2020

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Last modified June 13 03:46 EDT 2021. Contains 344980 sequences. (Running on oeis4.)