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 A081393 a(n) is the smallest x such that number of non-unitary prime divisors of central binomial coefficient, A000984(x)=C(2x,x) equals n. 2
 1, 3, 5, 14, 48, 74, 182, 314, 480, 774, 960, 1321, 1323, 1670, 3121, 3455, 3457, 3472, 3462, 3469, 8203, 9991 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(n) = Min{x; A081387(x)=n}. EXAMPLE n=5: a(5)=74, C(148,74) has 5 non-unitary prime divisors: {2,3,5,7,11} and 74 is the smallest. CROSSREFS Cf. A081387, A081394, A081395. Sequence in context: A230585 A006395 A078718 * A338368 A129326 A167553 Adjacent sequences:  A081390 A081391 A081392 * A081394 A081395 A081396 KEYWORD nonn,more AUTHOR Labos Elemer, Mar 27 2003 EXTENSIONS a(11)-a(21) from Michel Marcus, Sep 01 2019 STATUS approved

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Last modified January 19 16:16 EST 2021. Contains 340270 sequences. (Running on oeis4.)