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A081218 Greatest squarefree number not exceeding n-th prime power which is not prime. 2
1, 3, 7, 7, 15, 23, 26, 31, 47, 62, 79, 119, 123, 127, 167, 241, 255, 287, 341, 359, 511, 527, 623, 727, 839, 959, 1023, 1330, 1367, 1679, 1847, 2047, 2186, 2195, 2207, 2399, 2807, 3122, 3478, 3719, 4094, 4487, 4911, 5039, 5327, 6239, 6559, 6857, 6887, 7919 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = A070321(A025475(n)).

LINKS

Table of n, a(n) for n=1..50.

CROSSREFS

Cf. A081217.

Sequence in context: A060845 A059478 A175329 * A240422 A130003 A098581

Adjacent sequences:  A081215 A081216 A081217 * A081219 A081220 A081221

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 10 2003

STATUS

approved

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Last modified February 21 18:05 EST 2020. Contains 332107 sequences. (Running on oeis4.)