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A002121 a(0) = 1, a(1) = 0, a(2) = -1; for n >= 3, a(n) = - a(n-2) + Sum_{ primes p with 3 <= p <= n} a(n-p).
(Formerly M0023 N0005)
2
1, 0, -1, 1, 1, -1, 0, 2, 0, -2, 2, 4, -3, -2, 8, 1, -8, 8, 12, -11, -4, 25, 4, -24, 21, 40, -31, -16, 82, 14, -81, 71, 131, -99, -48, 258, 46, -249, 223, 422, -303, -162, 825, 169, -791, 714, 1360, -955, -503, 2641, 573, -2479, 2263, 4365, -2941, -1592, 8436, 1978, -7830, 7212, 14083, -9133, -4992, 26970, 6688, -24590 (list; graph; refs; listen; history; internal format)
OFFSET

0,8

COMMENTS

Arises in studying the Goldbach conjecture.

The last negative term appears to be a(303). - T. D. Noe, Dec 05 2006

REFERENCES

P. A. MacMahon, Properties of prime numbers deduced from the calculus of symmetric functions, Proc. London Math. Soc., 23 (1923), 290-316. [Coll. Papers, Vol. II, pp. 354-382] [The sequence g_n]

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

T. D. Noe, Table of n, a(n) for n=0..1000

FORMULA

G.f.: 1/(1+Sum_{k>0} (-x)^prime(k)). - Vladeta Jovovic (vladeta(AT)eunet.rs), Mar 29 2003

CROSSREFS

Cf. A002100-A002125.

Sequence in context: A157898 A137430 A181346 * A118658 A165912 A171936

Adjacent sequences:  A002118 A002119 A002120 * A002122 A002123 A002124

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Mar 29 2003

Entry revised by N. J. A. Sloane (njas(AT)research.att.com), Dec 04 2006

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Last modified February 15 13:35 EST 2012. Contains 205802 sequences.