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 A025556 a(n) = sum of the exponents in the prime factorization of LCM{1,3,6,...,C(n+1,2)}. 0
 0, 1, 2, 3, 3, 4, 5, 6, 6, 7, 7, 8, 8, 8, 9, 10, 10, 11, 11, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 27, 28, 28, 29, 29, 29, 29, 29, 29, 30 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS FORMULA a(n) = A001222(A025555(n)). - Sean A. Irvine, Sep 06 2019 PROG (PARI) a025555(n) = my(s=1); for(k=1, n, s=lcm(s, k*(k+1)/2)); s \\ after Edward Jiang in A025555 a(n) = bigomega(a025555(n)) \\ Felix FrÃ¶hlich, Sep 06 2019 CROSSREFS Cf. A001222, A025555. Sequence in context: A172104 A006161 A132351 * A338006 A005229 A091245 Adjacent sequences:  A025553 A025554 A025555 * A025557 A025558 A025559 KEYWORD nonn AUTHOR EXTENSIONS More terms from Sean A. Irvine, Sep 06 2019 STATUS approved

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Last modified September 27 15:28 EDT 2021. Contains 347691 sequences. (Running on oeis4.)