OFFSET
2,1
EXAMPLE
24 = 2^3 * 3^1. The prime factors have mean (2+3)/2 = 2 1/2, which rounds up to 3. The exponents have mean (3+1)/2 = 2. So a(24) = 3^2 = 9.
MAPLE
with(numtheory): for n from 2 to 100 do pmean := round(sum(ifactors(n)[2][i][1], i=1..nops(ifactors(n)[2]))/nops(ifactors(n)[2])): emean := round(sum(ifactors(n)[2][i][2], i=1..nops(ifactors(n)[2]))/nops(ifactors(n)[2])): printf(`%d, `, pmean^emean) od:
MATHEMATICA
a[n_] := Floor[1/2+(Plus@@First/@(fn=FactorInteger[n]))/(lth=Length[fn])]^Floor[1/2+(Plus@@Last/@fn)/lth]
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Joseph L. Pe, Feb 02 2002
EXTENSIONS
Edited by Dean Hickerson and James A. Sellers, Feb 12 2002
STATUS
approved