# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a053212 Showing 1-1 of 1 %I A053212 #20 Oct 27 2023 22:00:45 %S A053212 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 A053212 48,42,22,45,13,60,35,54,50,56,64,33,72,26,63,80,44,84,90,70,96,75,39, %U A053212 81,100,66,49,108,120,112,52,17,55,128,126,88,144,105,160 %N A053212 Number of divisors of the minimal numbers (A007416). %C A053212 A permutation of the natural numbers. %H A053212 T. D. Noe, Table of n, a(n) for n = 1..1000 %H A053212 Index entries for sequences that are permutations of the natural numbers %F A053212 a(n) = A000005(A007416(n)). - _Omar E. Pol_, Dec 26 2008 %t A053212 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 A053212 (Haskell) %o A053212 a053212 = a000005' . a007416 -- _Reinhard Zumkeller_, Apr 18 2015 %Y A053212 Cf. A007416, A005179. Inverse permutation to A064787. %Y A053212 Cf. A000005. - _Omar E. Pol_, Dec 26 2008 %K A053212 nonn,nice %O A053212 1,2 %A A053212 _Asher Auel_, Dec 16 1999 %E A053212 More terms from _Naohiro Nomoto_, Apr 03 2001 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE