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 A238689 Table read by rows: first row is {1}; for n >1, T(n, k) is the k-th largest prime factor of n (repeated prime factors are counted repeatedly). 3
 1, 2, 3, 2, 2, 5, 3, 2, 7, 2, 2, 2, 3, 3, 5, 2, 11, 3, 2, 2, 13, 7, 2, 5, 3, 2, 2, 2, 2, 17, 3, 3, 2, 19, 5, 2, 2, 7, 3, 11, 2, 23, 3, 2, 2, 2, 5, 5, 13, 2, 3, 3, 3, 7, 2, 2, 29, 5, 3, 2, 31, 2, 2, 2, 2, 2, 11, 3, 17, 2, 7, 5, 3, 3, 2, 2, 37, 19, 2, 13, 3, 5, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS n-th row has length 1 if n = 1, A001222(n) if n > 1. LINKS Peter Kagey, Table of n, a(n) for n = 1..10000 FORMULA Row n is row n of A027746 in reverse order. EXAMPLE Table begins: 1; 2; 3; 2,2; 5; 3,2; 7; 2,2,2; 3,3; 5,2; ... PROG (Haskell) a238689_row 1 = [1] a238689_row n = a n [] a000040_list where   a m factors ps@(p:ps')     | m == 1         = factors     | m `mod` p == 0 = a (m `div` p) (p : factors) ps     | otherwise      = a m           factors       ps' a _ _ [] = [] -- Peter Kagey, Sep 15 2016 CROSSREFS First column is A006530; numbers along right boundary form A020639. A001414 gives row sums (for n > 1). Cf. A027746, A238690. Sequence in context: A207338 A027746 A240230 * A166454 A283239 A318177 Adjacent sequences:  A238686 A238687 A238688 * A238690 A238691 A238692 KEYWORD nonn,tabf AUTHOR Matthew Vandermast, Apr 28 2014 STATUS approved

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Last modified December 11 10:48 EST 2018. Contains 318049 sequences. (Running on oeis4.)