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%I #20 Oct 27 2023 22:00:45
%S 1,2,3,4,6,5,8,9,10,12,7,16,15,18,14,20,24,21,30,32,27,28,11,36,25,40,
%T 48,42,22,45,13,60,35,54,50,56,64,33,72,26,63,80,44,84,90,70,96,75,39,
%U 81,100,66,49,108,120,112,52,17,55,128,126,88,144,105,160
%N Number of divisors of the minimal numbers (A007416).
%C A permutation of the natural numbers.
%H T. D. Noe, <a href="/A053212/b053212.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F a(n) = A000005(A007416(n)). - _Omar E. Pol_, Dec 26 2008
%t Reap[For[n = 1, n <= 10^5, n++, tau = DivisorSigma[0, n]; If[Abs[Product[DivisorSigma[0, k] - tau, {k, 1, n - 1}]] > 0, Print[tau]; Sow[tau]]]][[2, 1]] (* _Jean-François Alcover_, Jan 16 2013 *)
%o (Haskell)
%o a053212 = a000005' . a007416 -- _Reinhard Zumkeller_, Apr 18 2015
%Y Cf. A007416, A005179. Inverse permutation to A064787.
%Y Cf. A000005. - _Omar E. Pol_, Dec 26 2008
%K nonn,nice
%O 1,2
%A _Asher Auel_, Dec 16 1999
%E More terms from _Naohiro Nomoto_, Apr 03 2001
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