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 A088377 (Smallest prime-factor of n)^2. 6
 1, 4, 9, 4, 25, 4, 49, 4, 9, 4, 121, 4, 169, 4, 9, 4, 289, 4, 361, 4, 9, 4, 529, 4, 25, 4, 9, 4, 841, 4, 961, 4, 9, 4, 25, 4, 1369, 4, 9, 4, 1681, 4, 1849, 4, 9, 4, 2209, 4, 49, 4, 9, 4, 2809, 4, 25, 4, 9, 4, 3481, 4, 3721, 4, 9, 4, 25, 4, 4489, 4, 9, 4, 5041, 4, 5329, 4, 9, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = A000290(A020639(n)). LINKS Eric Weisstein's World of Mathematics, Least Prime Factor Eric Weisstein's World of Mathematics, Square Number CROSSREFS Cf. A088378, A088379. Cf. A068319. Cf. A247180. Sequence in context: A204996 A061369 A291645 * A066048 A103164 A210966 Adjacent sequences:  A088374 A088375 A088376 * A088378 A088379 A088380 KEYWORD nonn AUTHOR Reinhard Zumkeller, Sep 28 2003 STATUS approved

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Last modified December 12 18:24 EST 2018. Contains 318081 sequences. (Running on oeis4.)