This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A061708 Smallest number whose square has (2n - 1)^2 divisors. 0
 1, 6, 36, 216, 210, 7776, 46656, 1260, 1679616, 10077696, 7560, 362797056, 44100, 18480, 78364164096, 470184984576, 272160, 264600, 101559956668416, 1632960, 3656158440062976, 21936950640377856, 180180, 789730223053602816, 9261000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) <= 6^(n-1); 36^(n-1) has (2n-1)^2 divisors for all n. LINKS FORMULA a(n) = Min_{x : d(x^2) = (2n-1)^2}; a(n) = Min_{x : A000005(A000290(x)) = A000290(A005408(n))} EXAMPLE n = 8, a(8) = 1260 = 2*2*3*3*5*7 and d(1260^2) = d(2*2*2*2*3*3*3*3*5*5*7*7) = 225 = (2*8-1)^2. n = 14, a(14) = 18480 and d((2*2*2*2*2*2*2*2*3*5*7*11)^2) = 729 = (2*14-1)^2. CROSSREFS Cf. A000005, A000290, A005179, A005408, A016017, A025281, A048691. Sequence in context: A199525 A074436 A036162 * A216127 A124535 A267789 Adjacent sequences:  A061705 A061706 A061707 * A061709 A061710 A061711 KEYWORD nonn AUTHOR Labos Elemer, Jun 19 2001 EXTENSIONS More terms from David Wasserman, Jun 24 2002 Edited by Charlie Neder, Jun 03 2019 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 18 12:18 EDT 2019. Contains 328160 sequences. (Running on oeis4.)