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A061399 Number of nonsquarefree integers between primes p(n) and p(n+1). 4
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, 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, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000

EXAMPLE

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

PROG

(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

CROSSREFS

A005117, A013929.

Sequence in context: A062277 A204929 A118210 * A161856 A122944 A107688

Adjacent sequences:  A061396 A061397 A061398 * A061400 A061401 A061402

KEYWORD

nonn

AUTHOR

Labos Elemer, Jun 07 2001

STATUS

approved

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Last modified September 17 22:53 EDT 2019. Contains 327147 sequences. (Running on oeis4.)