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A061399 Number of nonsquarefree integers between primes p(n) and p(n+1). 4

%I

%S 0,1,0,2,1,1,1,1,4,0,2,1,0,2,4,2,1,2,1,1,2,2,2,3,3,0,1,1,1,7,1,3,0,4,

%T 1,3,2,1,4,2,1,3,1,1,1,4,3,2,1,1,2,1,6,2,2,2,1,3,2,0,4,6,1,1,2,4,3,5,

%U 1,3,1,4,3,3,1,3,2,1,3,3,1,4,1,1,2,2,3,2,0,1,5,3,2,3,1,3,4,1,9,1,5,2,3,0,3

%N Number of nonsquarefree integers between primes p(n) and p(n+1).

%H Harry J. Smith, <a href="/A061399/b061399.txt">Table of n, a(n) for n=1,...,1000</a>

%e Between 113 and 127 the 7 numbers which are not squarefree are {116,117,120,121,124,125,126}, so a(30)=7.

%o (PARI) { n=0; q=2; forprime (p=3, prime(1001), a=0; for (i=q+1, p-1, a+=!issquarefree(i)); write("b061399.txt", n++, " ", a); q=p ) } \\ _Harry J. Smith_, Jul 22 2009

%Y A005117, A013929.

%K nonn

%O 1,4

%A _Labos Elemer_, Jun 07 2001

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Last modified October 15 10:46 EDT 2019. Contains 328026 sequences. (Running on oeis4.)