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%I #12 Apr 28 2016 12:08:52
%S 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,
%T 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,
%U 5,7,11,13,17,2,3,7,11,13,17,19,2,3,5,11,13
%N 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.
%H Reinhard Zumkeller, <a href="/A256113/b256113.txt">b-file >>Rows n = 1..1000 of triangle, flattened</a>
%H <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a>
%e . n | T(n,k) | A001142(n) | A007318(n,0..n)
%e . ---+------------+---------------------------+-------------------------
%e . 1 | 1 | 1 | 1 1
%e . 2 | 2 | 2 | 1 2 1
%e . 3 | 3 | 9 | 1 3 3 1
%e . 4 | 2 3 | 96 | 1 4 6 4 1
%e . 5 | 2 5 | 2500 | 1 5 10 10 5 1
%e . 6 | 2 3 5 | 162000 | 1 6 15 20 15 6 1
%e . 7 | 3 5 7 | 26471025 | 1 7 21 35 35 21 7 1
%e . 8 | 2 5 7 | 11014635520 | 1 8 28 56 70 56 28 ...
%e . 9 | 2 3 7 | 11759522374656 | 1 9 36 84 126 126 84 ...
%e . 10 | 2 3 5 7 | 32406091200000000 | 1 10 45 120 210 252 210 ...
%e . 11 | 2 3 5 7 11 | 231627686043080250000 | 1 11 55 165 330 462 462 ...
%e . 12 | 2 3 5 7 11 | 4311500661703860387840000 | 1 12 66 220 495 792 924 ...
%o (Haskell)
%o a256113 n k = a256113_tabf !! (n-1) !! (n-1)
%o a256113_row n = a256113_tabf !! (n-1)
%o a256113_tabf = map a027748_row $ tail a001142_list
%Y Cf. A007318, A027748, A001142, A004788 (row lengths), A056606 (row products).
%K nonn,tabf
%O 1,2
%A _Reinhard Zumkeller_, Mar 16 2015