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A001172 Smallest even number that is an unordered sum of two odd primes in exactly n ways.
(Formerly M4085 N1694)
16
0, 6, 10, 22, 34, 48, 60, 78, 84, 90, 114, 144, 120, 168, 180, 234, 246, 288, 240, 210, 324, 300, 360, 474, 330, 528, 576, 390, 462, 480, 420, 570, 510, 672, 792, 756, 876, 714, 798, 690, 1038, 630, 1008, 930, 780, 960, 870, 924, 900, 1134, 1434, 840, 990, 1302 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
a(n) = A023036(n) for all n > 1.
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
Eric Wolman, Letter to N. J. A. Sloane, 1970.
MATHEMATICA
nn = 55; a = Table[0, {nn}]; n = 6; While[Times @@ a == 0, c = 0; k = 3; While[k <= n/2, If[PrimeQ[k] && PrimeQ[n - k], c++]; k++]; If[c <= nn && a[[c]] == 0, a[[c]] = n]; n = n + 2]; Prepend[a, 0]
CROSSREFS
Divided by 2: A258713.
Sequence in context: A189992 A255746 A082917 * A339437 A108605 A216049
KEYWORD
nonn,nice,look,easy
AUTHOR
N. J. A. Sloane, Eric Wolman, Dec 17 1969
EXTENSIONS
a(0) corrected by Zak Seidov, Sep 30 2011
STATUS
approved

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Last modified March 28 05:02 EDT 2024. Contains 371235 sequences. (Running on oeis4.)