A111260 Numbers of the form (m^n)/(n^m) with m > 0 and n>1.

1, 4, 16, 27, 256, 729, 65536, 2985984, 4194304, 9765625, 134217728, 387420489, 2176782336, 24794911296, 30517578125, 104857600000, 678223072849, 2641807540224, 7625597484987, 17592186044416, 281474976710656

Offset

1,2

Links

Table of n, a(n) for n=1..21.

Example

The 4th element is a=27 with m = 3 and n = 9 because 3^9/9^3 = 27.

Maple

a:=proc(N) local a, m, n; for m from 1 to N do for n from 2 to N do a:=(m^n)/(n^m); if(floor(a)=a)then print(a) fi; od; od; end: # convert into set # sort set

Mathematica

Take[ Select[ Union@Flatten@Table[(m^n)/(n^m), {m, 35}, {n, 2, 35}], IntegerQ[ # ] &], 21] (* Robert G. Wilson v, Nov 17 2005 *)

Crossrefs

Cf. A072651, A072652, A072653.

Sequence in context: A368107 A008478 A201009 * A067688 A097374 A257309

Adjacent sequences: A111257 A111258 A111259 * A111261 A111262 A111263

Keyword

nonn

Author

Giorgio Balzarotti and Paolo P. Lava, Nov 12 2005

Status

approved