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 A120358 Even refactorable numbers n such that the number r of odd divisors and the number s of even divisors are both odd divisors of n and n is the first number for which the triple (r,s,t) occurs, where t is the number of divisors of n. 1
 2, 18, 72, 450, 1250, 4050, 16200, 52488, 56448, 64800, 71442, 101250, 198450, 235298, 285768, 328050, 405000, 793800, 1036800, 1312200, 1620000, 1786050, 3175200, 4572288, 4961250, 5248800 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Note that s is necessarily a multiple of r. LINKS Table of n, a(n) for n=1..26. EXAMPLE a(2)=18 since r=3, s=3 and r+s=6. CROSSREFS Cf. A033950, A049439. A057265. Sequence in context: A163102 A073976 A120361 * A152887 A098817 A197093 Adjacent sequences: A120355 A120356 A120357 * A120359 A120360 A120361 KEYWORD nonn AUTHOR Walter Kehowski, Jun 25 2006 STATUS approved

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Last modified September 23 17:42 EDT 2023. Contains 365554 sequences. (Running on oeis4.)