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A205617
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Number of decompositions of 2n into an unordered sum of two non-Ramanujan primes (A174635).
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3
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0, 0, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 2, 2, 1, 2, 2, 2, 1, 3, 0, 1, 3, 1, 2, 2, 1, 3, 2, 0, 1, 3, 2, 1, 3, 1, 3, 4, 1, 2, 4, 1, 4, 2, 0, 3, 2, 3, 2, 3, 2, 3, 5, 1, 3, 4, 0, 5, 1, 0, 4, 3, 3, 1, 4, 3, 5, 4, 0, 4, 3, 1, 4, 2, 2, 6, 2, 3, 4, 4, 1, 3
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OFFSET
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1,5
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COMMENTS
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There are 15 zeros in the first 10^8 terms. a(n) > 0 for n from 315 to 10^8.
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LINKS
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EXAMPLE
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a(25) = 3. 2*25 = 50 = 7+43 = 13+37 = 19+31 (7, 13, 19, 31, 37, and 43 are all non-Ramanujan primes (A174635)). 50 is the unordered sum of two non-Ramanujan primes in three ways.
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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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