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A111260 Numbers of the form (m^n)/(n^m) with m > 0 and n>1. 0
1, 4, 16, 27, 256, 729, 65536, 2985984, 4194304, 9765625, 134217728, 387420489, 2176782336, 24794911296, 30517578125, 104857600000, 678223072849, 2641807540224, 7625597484987, 17592186044416, 281474976710656 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

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] (from Robert G. Wilson v (rgwv(at)rgwv.com), Nov 17 2005)

CROSSREFS

Cf. A072651 A072652 A072653.

Sequence in context: A072873 A072653 A008478 * A067688 A046358 A046366

Adjacent sequences:  A111257 A111258 A111259 * A111261 A111262 A111263

KEYWORD

nonn

AUTHOR

Giorgio Balzarotti (greenblue(AT)tiscali.it) and Paolo P. Lava (paoloplava(AT)gmail.com), Nov 12 2005

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.