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 A256015 Triangle read by rows: n-th row contains all distinct primes which are representable as the sum of some subset of the set of first n primes. 3
 2, 2, 3, 5, 2, 3, 5, 7, 2, 3, 5, 7, 17, 2, 3, 5, 7, 11, 13, 17, 19, 23, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A066028(n) = T(n,A108018(n)). LINKS Reinhard Zumkeller, Rows n = 1..25 of triangle, flattened EXAMPLE .  1:  2 | .  2:  2 3 | 5 .  3:  2 3 5 | 7 .  4:  2 3 5 7 | 17 .  5:  2 3 5 7 11 | 13  17  19  23 .  6:  2 3 5 7 11 13 | 17  19  23  29  31  41 .  7:  2 3 5 7 11 13 17 | 19  23  29  31  37  41  43  47  53 .  8:  2 3 5 7 11 13 17 19 | 23  29  31  37  41  43  47  53  59  61  67 . PROG (Haskell) import Data.List (subsequences, nub, sort) a256015 n k = a256015_tabf !! (n-1) !! (k-1) a256015_row n = a256015_tabf !! (n-1) a256015_tabf = map (sort . filter ((== 1) . a010051') . nub .                 map sum . tail . subsequences) (tail \$ inits a000040_list) CROSSREFS Cf. A010051, A000040, A108018 (row lengths), A066028 (right edge). Sequence in context: A140183 A280408 A130725 * A138117 A175908 A152430 Adjacent sequences:  A256012 A256013 A256014 * A256016 A256017 A256018 KEYWORD nonn,tabf AUTHOR Reinhard Zumkeller, Jun 01 2015 STATUS approved

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Last modified December 9 23:01 EST 2019. Contains 329880 sequences. (Running on oeis4.)