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 A248141 Table read by rows: n-th row contains all subsets of consecutive numbers of 1..n. 3
 1, 1, 2, 1, 2, 1, 2, 3, 1, 2, 2, 3, 1, 2, 3, 1, 2, 3, 4, 1, 2, 2, 3, 3, 4, 1, 2, 3, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 5, 1, 2, 2, 3, 3, 4, 4, 5, 1, 2, 3, 2, 3, 4, 3, 4, 5, 1, 2, 3, 4, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 6, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS A000292(n) = length of n-th row, whereas A000217(n) = number of all consecutive subsets of numbers 1..n; A248147(n,k) = A000040(T(n,k)), 1 <= k <= A000292(n). LINKS Reinhard Zumkeller, Rows n = 1..20 of triangle, flattened EXAMPLE .  1: 1 .  2: 1,2,1,2 .  3: 1,2,3,1,2,2,3,1,2,3 .  4: 1,2,3,4,1,2,2,3,3,4,1,2,3,2,3,4,1,2,3,4 .  5: 1,2,3,4,5,1,2,2,3,3,4,4,5,1,2,3,2,3,4,3,4,5,1,2,3,4,2,3,4,5,1,2,3,4,5 rows concatenated from: .  1: [1] .  2: [1] [2] [1,2] .  3: [1] [2] [3] [1,2] [2,3] [1,2,3] .  4: [1] [2] [3] [4] [1,2] [2,3] [3,4] [1,2,3] [2,3,4] [1,2,3,4] .  5: [1] [2] [3] [4] [5] [1,2] [2,3] [3,4] [4,5] [1,2,3] [2,3,4] ... MATHEMATICA Flatten[Table[Flatten[Table[Partition[Range[n], i, 1], {i, n}]], {n, 6}]] (* Harvey P. Dale, Feb 03 2015 *) PROG (Haskell) import Data.List (group) a248141 n k = a248141_tabf !! (n-1) !! (k-1) a248141_row n = a248141_tabf !! (n-1) a248141_tabf = map concat usss where    usss = iterate f [[1]] where      f vss = group [1 .. last (last vss) + 1] ++              map (\ws -> ws ++ [last ws + 1]) vss CROSSREFS Cf. A000292 (row lengths), A000217, A248147. Sequence in context: A105265 A193360 A061394 * A220694 A136314 A121997 Adjacent sequences:  A248138 A248139 A248140 * A248142 A248143 A248144 KEYWORD nonn,tabf AUTHOR Reinhard Zumkeller, Oct 02 2014 STATUS approved

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Last modified August 16 23:58 EDT 2018. Contains 313809 sequences. (Running on oeis4.)