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 A051466 Largest product of primorials less than A025487(n) that divides A025487(n). 2
 1, 2, 2, 4, 6, 8, 12, 6, 16, 12, 24, 30, 32, 36, 48, 60, 64, 72, 60, 96, 30, 72, 120, 128, 144, 180, 192, 210, 216, 240, 256, 288, 360, 384, 420, 432, 180, 480, 512, 360, 576, 420, 432, 720, 768, 840, 864, 900, 960, 1024, 1080, 1152, 210, 1260, 1296, 1440 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 COMMENTS Note that A036041(A025487(n)) = A036041(a(n)) + 1 since A025487(n)/a(n) is prime. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 2..10000 FORMULA a(n) = A025487(n) / p, where p is the largest prime such that p^A051282(n) | A025487(n). - Charlie Neder, Oct 12 2018 EXAMPLE A025487 = 1, 2, 4, 6, 8, 12, 16, 24, 30, 32, 36, ...; a(n)= 1, 2, 2, 4, 6, 8, 12, 6, 16, 12, ... . (12 divides 36, but 16 through 32 do not.) A025487(38) = 900 = 5#*5#. The largest product of primorials that divides this number will be 5#*3# = 180 = a(38). - Charlie Neder, Oct 20 2018 MATHEMATICA (* First, load second program at A025487, then: *) With[{s = Union@ Flatten@ f[5]}, Table[SelectFirst[Reverse@ Take[s, n - 1], Mod[s[[n]], #] == 0 &], {n, 2, Length@ s}]] (* Michael De Vlieger, Dec 27 2019 *) PROG (Haskell) a051466 n = a051466_list !! (n-2) a051466_list = f [head a025487_list] \$ tail a025487_list where    f us (v:vs) = fromJust (find (\x -> mod v x == 0) us) : f (v : us) vs -- Reinhard Zumkeller, Jul 17 2013 CROSSREFS Cf. A036041, A034776. Sequence in context: A258125 A147982 A329899 * A320193 A260215 A261156 Adjacent sequences:  A051463 A051464 A051465 * A051467 A051468 A051469 KEYWORD easy,nice,nonn AUTHOR EXTENSIONS Offset updated by Matthew Vandermast, Jul 03 2012 Name edited by Charlie Neder, Oct 20 2018 Name clarified by Antti Karttunen, Dec 24 2019 STATUS approved

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Last modified August 3 07:58 EDT 2021. Contains 346435 sequences. (Running on oeis4.)