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%I #15 Mar 12 2019 09:20:35
%S 1,3,4,5,9,12,16,19,25,31,37,43,51,59,66,75,84,95,103,115,127,137,150,
%T 162,177,191,205,218,233,250,267,282,299,319,338,359,376,399,421,440,
%U 461,481,508,531,556,578,602,629,653,683,707,737,765,793,824,853,883
%N a(n) = the number of primes representable as the sum of some subset of the set of first n primes.
%C a(n) = length of n-th row in A256015; A066028(n) = A256015(n,a(n)). - _Reinhard Zumkeller_, Jun 01 2015
%H Alois P. Heinz, <a href="/A108018/b108018.txt">Table of n, a(n) for n = 1..500</a>
%t (* This program is not suitable to compute a large number of terms. *)
%t a[n_] := a[n] = Select[Total /@ Subsets[Table[Prime[i], {i, 1, n}]], PrimeQ] // Union // Length;
%t Table[Print[n, " ", a[n]]; a[n], {n, 1, 25}] (* _Jean-François Alcover_, Mar 12 2019 *)
%o (Haskell)
%o import Data.List (subsequences, nub)
%o a108018 = sum . map a010051' . nub . map sum .
%o tail . subsequences . flip take a000040_list
%o -- _Reinhard Zumkeller_, Dec 16 2013
%Y Cf. A071810 (same count but with multiplicities).
%Y Cf. A010051, A000040.
%Y Cf. A066028, A256015.
%K nonn
%O 1,2
%A _Max Alekseyev_, Sep 08 2006
%E More terms from _Alois P. Heinz_, Oct 24 2015
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