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A340965
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Number of ways to write n as an ordered sum of 9 primes.
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11
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1, 9, 36, 93, 198, 387, 696, 1170, 1845, 2740, 3960, 5562, 7566, 10125, 13248, 17133, 22014, 27774, 34776, 43173, 53010, 64869, 78696, 94617, 113415, 134946, 159552, 188164, 219960, 256041, 297180, 342846, 394614, 452595, 516276, 587997, 667938, 755109, 852444
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OFFSET
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18,2
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LINKS
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FORMULA
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G.f.: (Sum_{k>=1} x^prime(k))^9.
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MAPLE
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b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 9):
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MATHEMATICA
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nmax = 56; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^9, {x, 0, nmax}], x] // Drop[#, 18] &
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CROSSREFS
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Cf. A000040, A010051, A073610, A098238, A259200, A340960, A340961, A340962, A340963, A340964, A340966.
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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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