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A087618 a(n) is the number of pair of consecutive numbers (k,k+1) with k<=10^n such that k and k+1 are both squarefree. 4
1, 5, 33, 323, 3230, 32269, 322619, 3226343, 32263377, 322634281, 3226340896, 32263409594, 322634100659, 3226340989192 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..13.

Eric Weisstein's World of Mathematics, Squarefree

FORMULA

Asymptotic density is A065474.

CROSSREFS

Cf. A071172, A065474.

Sequence in context: A084845 A198079 A098460 * A322178 A134152 A140424

Adjacent sequences:  A087615 A087616 A087617 * A087619 A087620 A087621

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Sep 19 2003

EXTENSIONS

a(11)-a(13) from Donovan Johnson, Jun 26 2010

STATUS

approved

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Last modified January 29 04:46 EST 2020. Contains 331335 sequences. (Running on oeis4.)