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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.)