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 A256113 Table read by rows: T(1,1) = 1, for n > 1: row n = union of distinct prime factors occurring in terms of n-th row of Pascal's triangle, cf. A007318. 5
 1, 2, 3, 2, 3, 2, 5, 2, 3, 5, 3, 5, 7, 2, 5, 7, 2, 3, 7, 2, 3, 5, 7, 2, 3, 5, 7, 11, 2, 3, 5, 7, 11, 2, 3, 5, 11, 13, 2, 3, 7, 11, 13, 3, 5, 7, 11, 13, 2, 3, 5, 7, 11, 13, 2, 5, 7, 11, 13, 17, 2, 3, 5, 7, 11, 13, 17, 2, 3, 7, 11, 13, 17, 19, 2, 3, 5, 11, 13 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Reinhard Zumkeller, b-file  >>Rows n = 1..1000 of triangle, flattened EXAMPLE .  n |   T(n,k)   |                A001142(n) | A007318(n,0..n) . ---+------------+---------------------------+------------------------- .  1 | 1          |                         1 | 1  1 .  2 | 2          |                         2 | 1  2  1 .  3 | 3          |                         9 | 1  3  3   1 .  4 | 2 3        |                        96 | 1  4  6   4   1 .  5 | 2 5        |                      2500 | 1  5 10  10   5   1 .  6 | 2 3 5      |                    162000 | 1  6 15  20  15   6   1 .  7 | 3 5 7      |                  26471025 | 1  7 21  35  35  21   7   1 .  8 | 2 5 7      |               11014635520 | 1  8 28  56  70  56  28 ... .  9 | 2 3 7      |            11759522374656 | 1  9 36  84 126 126  84 ... . 10 | 2 3 5 7    |         32406091200000000 | 1 10 45 120 210 252 210 ... . 11 | 2 3 5 7 11 |     231627686043080250000 | 1 11 55 165 330 462 462 ... . 12 | 2 3 5 7 11 | 4311500661703860387840000 | 1 12 66 220 495 792 924 ... PROG (Haskell) a256113 n k = a256113_tabf !! (n-1) !! (n-1) a256113_row n = a256113_tabf !! (n-1) a256113_tabf = map a027748_row \$ tail a001142_list CROSSREFS Cf. A007318, A027748, A001142, A004788 (row lengths), A056606 (row products). Sequence in context: A086757 A166985 A046215 * A256368 A057019 A084740 Adjacent sequences:  A256110 A256111 A256112 * A256114 A256115 A256116 KEYWORD nonn,tabf AUTHOR Reinhard Zumkeller, Mar 16 2015 STATUS approved

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Last modified April 17 10:52 EDT 2021. Contains 343064 sequences. (Running on oeis4.)