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A079229
Least k>0 such that rad(n+k) > rad(n), where rad is the squarefree kernel (A007947).
2
1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 3, 2, 1, 3, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 4, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 3, 2, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 2, 1, 4, 1, 2, 1, 1, 1, 2, 1, 1
OFFSET
1,3
COMMENTS
A020754 probably gives the records in this sequence. - Charles R Greathouse IV, Aug 02 2013
LINKS
MATHEMATICA
rad[n_] := Times @@ FactorInteger[n][[All, 1]]; a[1] = 1; a[n_] := For[k = 1, True, k++, If[ rad[n+k] > rad[n], Return[k]]]; Table[ a[n], {n, 1, 105}] (* Jean-François Alcover, Oct 05 2012 *)
PROG
(Haskell)
a079229 n = a079229_list !! (n-1)
a079229_list = f a007947_list where
f (x:xs) = ((+ 1) . length $ takeWhile (<= x) xs) : f xs
-- Reinhard Zumkeller, Oct 06 2012
(PARI) rad(n)=my(f=factor(n)[, 1]); prod(i=1, #f, f[i])
a(n)=my(r=rad(n), k); while(r>=rad(n+k++), ); k \\ Charles R Greathouse IV, Aug 02 2013
CROSSREFS
a(n) = A079228(n) - n.
Sequence in context: A237513 A137844 A263845 * A344972 A204988 A368332
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 02 2003
STATUS
approved