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A098238
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Number of ordered ways of writing n as sum of three primes.
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4
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0, 0, 0, 0, 0, 0, 1, 3, 3, 4, 6, 6, 9, 6, 6, 10, 9, 12, 12, 12, 12, 19, 12, 21, 15, 21, 18, 30, 15, 30, 12, 30, 18, 37, 12, 39, 21, 42, 24, 46, 9, 51, 18, 48, 24, 54, 18, 66, 21, 60, 30, 67, 24, 81, 18, 75, 30, 79, 18, 87, 21, 87, 36, 93, 15, 105, 30, 105, 36, 97, 12, 120, 30, 114, 36
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,8
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..10000
P. Pollack, Analytic and Combinatorial Number Theory Course Notes, p. 213. [?Broken link]
P. Pollack, Analytic and Combinatorial Number Theory Course Notes, p. 213.
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FORMULA
| G.f.: (Sum_{k>0} x^prime(k))^3. - Vladeta Jovovic (vladeta(AT)eunet.rs), Mar 12 2005
Third convolution of "a(n)=1 if n prime, 0 otherwise" (A010051) with itself. - Graeme McRae (g_m(AT)mcraefamily.com), Jul 18 2006
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MAPLE
| t1:=add(q^ithprime(n), n=1..1000): series(t1^3, q, 1001): seriestolist(%); - N. J. A. Sloane (njas(AT)research.att.com), Sep 29 2006
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CROSSREFS
| Cf. A073610, A014612.
Cf. A068307
Sequence in context: A092200 A130481 A145805 * A088651 A161019 A137901
Adjacent sequences: A098235 A098236 A098237 * A098239 A098240 A098241
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KEYWORD
| nonn
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AUTHOR
| Ralf Stephan, Aug 31 2004
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