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A058698
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a(n) = p(P(n)), P = primes (A000040), p = partition numbers (A000041).
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18
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2, 3, 7, 15, 56, 101, 297, 490, 1255, 4565, 6842, 21637, 44583, 63261, 124754, 329931, 831820, 1121505, 2679689, 4697205, 6185689, 13848650, 23338469, 49995925, 133230930, 214481126, 271248950, 431149389, 541946240, 851376628, 3913864295, 5964539504, 11097645016
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OFFSET
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1,1
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COMMENTS
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Number of partitions of n-th prime. - Omar E. Pol, Aug 05 2011
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LINKS
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FORMULA
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EXAMPLE
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a(2) = 3 because the second prime is 3 and there are three partitions of 3: {1, 1, 1}, {1, 2}, {3}.
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MATHEMATICA
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PROG
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(Haskell)
import Data.MemoCombinators (memo2, integral)
a058698 n = a058698_list !! (n-1)
a058698_list = map (pMemo 1) a000040_list where
pMemo = memo2 integral integral p
p _ 0 = 1
p k m | m < k = 0
| otherwise = pMemo k (m - k) + pMemo (k + 1) m
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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