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A002122
a(n) = Sum_{t=0..n} g(t)*g(n-t) where g(t) = A002121(t).
(Formerly M0273 N0096)
1
1, 0, -2, 2, 3, -4, -1, 8, -1, -10, 9, 16, -18, -12, 42, 4, -58, 40, 82, -88, -54, 188, 18, -248, 151, 354, -338, -260, 760, 120, -1031, 574, 1460, -1324, -1076, 2948, 542, -3962, 2075, 5644, -4868, -4290, 11035, 2418, -14900, 7346, 21300, -17652, -16323, 40442, 9768, -54476, 25675, 78290, -62456
OFFSET
0,3
COMMENTS
Arises in studying the Goldbach conjecture.
The last negative term appears to be a(485). - T. D. Noe, Dec 05 2006
REFERENCES
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
P. A. MacMahon, Properties of prime numbers deduced from the calculus of symmetric functions, Proc. London Math. Soc., 23 (1923), 290-316. = Coll. Papers, II, pp. 354-380. [The sequence G_n]
FORMULA
G.f.: 1/(1+Sum_{k>0} (-x)^prime(k))^2.
PROG
(Haskell)
a002122 n = a002122_list !! n
a002122_list = uncurry conv $ splitAt 1 a002121_list where
conv xs (z:zs) = sum (zipWith (*) xs $ reverse xs) : conv (z:xs) zs
-- Reinhard Zumkeller, Mar 21 2014
CROSSREFS
Cf. A002121.
Sequence in context: A008951 A119473 A336889 * A105689 A351080 A187200
KEYWORD
sign
EXTENSIONS
Edited by Vladeta Jovovic, Mar 29 2003
Entry revised by N. J. A. Sloane, Dec 04 2006
STATUS
approved