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A122464
Smooth Power Trios: a(n) is the largest of three successive numbers a(n)-j, j=0..2, such that the largest prime factor of a(n)-j is <= the n-th root of a(n)-j.
2
4, 50, 134850, 116026275, 138982583000, 1348770149848002
OFFSET
1,1
COMMENTS
The fifth term was found by R. Gerbicz, the others were found by F. Schneider.
LINKS
Fred Schneider and R. Gerbicz, Smooth Power Trios.
EXAMPLE
Example for n=6:
1348770149848002 = 2 x 3 x 7 x 23 x 41 x 61^2 x 149 x 239 x 257,
1348770149848001 = 19^3 x 89 x 103 x 229 x 283 x 331,
1348770149848000 = 2^6 x 5^3 x 11 x 29 x 109 x 151 x 163 x 197,
This satisfies because 331 <= floor(1348770149848000^(1/6)) = 332.
CROSSREFS
Sequence in context: A193157 A235604 A221477 * A226375 A347551 A048995
KEYWORD
hard,more,nonn
AUTHOR
Fred Schneider, Sep 09 2006
STATUS
approved