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A340963
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Number of ways to write n as an ordered sum of 7 primes.
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11
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1, 7, 21, 42, 77, 133, 210, 316, 434, 574, 770, 980, 1239, 1547, 1876, 2331, 2828, 3367, 4032, 4746, 5565, 6574, 7602, 8757, 10136, 11480, 13132, 14882, 16646, 18662, 20951, 23268, 26082, 28861, 31787, 35218, 38745, 42532, 46403, 50883, 54810, 60613, 65016, 71302, 76069
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OFFSET
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14,2
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LINKS
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FORMULA
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G.f.: (Sum_{k>=1} x^prime(k))^7.
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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, 7):
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MATHEMATICA
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nmax = 58; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^7, {x, 0, nmax}], x] // Drop[#, 14] &
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CROSSREFS
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Cf. A000040, A010051, A073610, A098238, A259197, A340960, A340961, A340962, A340964, A340965, 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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