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 A248164 Table read by rows: n-th row contains the products of all consecutive subsets of the first n primes in their natural order. 3
 2, 2, 3, 6, 2, 3, 5, 6, 15, 30, 2, 3, 5, 7, 6, 15, 35, 30, 105, 210, 2, 3, 5, 7, 11, 6, 15, 35, 77, 30, 105, 385, 210, 1155, 2310, 2, 3, 5, 7, 11, 13, 6, 15, 35, 77, 143, 30, 105, 385, 1001, 210, 1155, 5005, 2310, 15015, 30030, 2, 3, 5, 7, 11, 13, 17, 6, 15 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS T(n,A000217(n)) = A002110(n). LINKS Reinhard Zumkeller, Rows n = 1..25 of triangle, flattened EXAMPLE .  1:  2 .  2:  2,3,6 .  3:  2,3,5,6,15,30 .  4:  2,3,5,7,6,15,35,30,105,210 .  5:  2,3,5,7,11,6,15,35,77,30,105,385,210,1155,2310 .  6:  2,3,5,7,11,13,6,15,35,77,143,30,105,385,1001,210,1155,5005,2310,15015,30030 The prime factors of these terms form consecutive primes, see also A248147. .  1: [2] .  2: [2] [3] [2,3] .  3: [2] [3] [5] [2,3] [3,5] [2,3,5] .  4: [2] [3] [5] [7] [2,3] [3,5] [5,7] [2,3,5] [3,5,7] [2,3,5,7] .  5: [2] [3] [5] [7] [11] [2,3] [3,5] [5,7] [7,11] [2,3,5] [3,5,7] ... .  6: [2] [3] [5] [7] [11] [13] [2,3] [3,5] [5,7] [7,11] [11,13] [2,3,5] ... PROG (Haskell) import Data.List (group) a248164 n k = a248164_tabf !! (n-1) !! (k-1) a248164_row n = a248164_tabf !! (n-1) a248164_tabf = map (map product) psss where    psss = iterate f [[2]] where       f pss = group (h \$ last pss) ++ map h pss       h ws = ws ++ [a151800 \$ last ws] CROSSREFS Cf. A000217 (row lengths), A002110, A151800, A248147. Sequence in context: A093422 A297890 A083506 * A210222 A207621 A209157 Adjacent sequences:  A248161 A248162 A248163 * A248165 A248166 A248167 KEYWORD nonn,tabf,look AUTHOR Reinhard Zumkeller, Oct 02 2014 STATUS approved

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Last modified October 20 20:18 EDT 2019. Contains 328273 sequences. (Running on oeis4.)