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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.

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%I A256015 #11 Apr 28 2016 11:33:26
%S A256015 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,
%T A256015 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,
%U A256015 11,13,17,19,23,29,31,37,41,43,47,53,59,61,67
%N 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.
%C A256015 A066028(n) = T(n,A108018(n)).
%H A256015 Reinhard Zumkeller, <a href="/A256015/b256015.txt">Rows n = 1..25 of triangle, flattened</a>
%e A256015 .  1:  2 |
%e A256015 .  2:  2 3 | 5
%e A256015 .  3:  2 3 5 | 7
%e A256015 .  4:  2 3 5 7 | 17
%e A256015 .  5:  2 3 5 7 11 | 13  17  19  23
%e A256015 .  6:  2 3 5 7 11 13 | 17  19  23  29  31  41
%e A256015 .  7:  2 3 5 7 11 13 17 | 19  23  29  31  37  41  43  47  53
%e A256015 .  8:  2 3 5 7 11 13 17 19 | 23  29  31  37  41  43  47  53  59  61  67 .
%o A256015 (Haskell)
%o A256015 import Data.List (subsequences, nub, sort)
%o A256015 a256015 n k = a256015_tabf !! (n-1) !! (k-1)
%o A256015 a256015_row n = a256015_tabf !! (n-1)
%o A256015 a256015_tabf = map (sort . filter ((== 1) . a010051') . nub .
%o A256015                 map sum . tail . subsequences) (tail $ inits a000040_list)
%Y A256015 Cf. A010051, A000040, A108018 (row lengths), A066028 (right edge).
%K A256015 nonn,tabf
%O A256015 1,1
%A A256015 _Reinhard Zumkeller_, Jun 01 2015