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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
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: A369690 A166985 A046215 * A256368 A057019 A084740
KEYWORD
nonn,tabf
AUTHOR
Reinhard Zumkeller, Mar 16 2015
STATUS
approved

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Last modified March 19 06:32 EDT 2024. Contains 370953 sequences. (Running on oeis4.)