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 A261153 a(n) is the maximum number of distinct primes whose sum is n. 0
 0, 0, 1, 1, 0, 2, 0, 2, 2, 2, 3, 1, 3, 2, 3, 3, 3, 4, 3, 3, 3, 4, 3, 4, 3, 4, 4, 4, 5, 4, 5, 4, 4, 4, 5, 4, 5, 4, 5, 5, 5, 6, 5, 5, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 6, 6, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS a(A007504(k)) = k. a(n) < k when n < A007504(k). Let pi(j) be the j-th prime. Then a(A007504(k) - pi(j)) = k-1, j<=k. For example, k=5: A007504(5) = 28, pi(5)=11. So a(n)=4, n = {26,25,23,21,17}. Similarly, a(A007504(k) + pi(j)) = k+1, where j>k and A007504(k) + pi(j) < A007504(k+2). For example, k=8: A007504(8) = 77, A007504(10) = 129 and pi(8)=19. Therefore, a(n)=9, n = {100,106,108,114,118,120,124}. LINKS EXAMPLE a(26)=4 because 3+5+7+11 = 26. Note that some terms may be expressed in multiple ways. For example, a(47)=6: 2+3+5+7+11+19 and 2+3+5+7+13+17 = 47. CROSSREFS Cf. A000040 (prime numbers), A007504. Sequence in context: A278248 A036461 A244478 * A199123 A325589 A291308 Adjacent sequences:  A261150 A261151 A261152 * A261154 A261155 A261156 KEYWORD nonn,easy AUTHOR Bob Selcoe, Aug 10 2015 STATUS approved

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Last modified May 22 19:19 EDT 2019. Contains 323481 sequences. (Running on oeis4.)