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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

A020754 probably gives the records in this sequence. - Charles R Greathouse IV, Aug 02 2013

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

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-Fran├žois 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: A175788 A237513 A137844 * A204988 A224765 A160267

Adjacent sequences:  A079226 A079227 A079228 * A079230 A079231 A079232

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jan 02 2003

STATUS

approved

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Last modified November 23 22:48 EST 2014. Contains 249866 sequences.