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A098238 Number of ordered ways of writing n as sum of three primes. 22
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; text; internal format)
OFFSET
0,8
LINKS
P. Pollack, Analytic and Combinatorial Number Theory Course Notes, p. 213. [?Broken link]
P. Pollack, Analytic and Combinatorial Number Theory Course Notes, p. 213.
FORMULA
G.f.: (Sum_{k>0} x^prime(k))^3. - Vladeta Jovovic, Mar 12 2005
Third convolution of "a(n)=1 if n prime, 0 otherwise" (A010051) with itself. - Graeme McRae, Jul 18 2006
MAPLE
t1:=add(q^ithprime(n), n=1..1000): series(t1^3, q, 1001): seriestolist(%); # N. J. A. Sloane, Sep 29 2006
MATHEMATICA
nn = 74; a = Sum[x^p, {p, Prime[Range[nn]]}]; CoefficientList[Series[a^3, {x, 0, nn}], x] (* Geoffrey Critzer, Jan 25 2015 *)
CROSSREFS
Cf. A068307.
Sequence in context: A130481 A145805 A277192 * A088651 A161019 A137901
KEYWORD
nonn
AUTHOR
Ralf Stephan, Aug 31 2004
STATUS
approved

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Last modified March 19 04:26 EDT 2024. Contains 370952 sequences. (Running on oeis4.)