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A023036 Smallest positive even integer that is an unordered sum of two primes in exactly n ways. 14
2, 4, 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, 1080 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Except for first two terms, same as A001172.

The first occurrence of k in A045917.

LINKS

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

Index entries for sequences related to Goldbach conjecture

EXAMPLE

a(3) = 22 as 22 = (19+3) = (17+5)= ( 11+11). There are exactly 3 ways 22 can be expressed as the sum of two primes and no even number less than 22 can be so expressed.

MATHEMATICA

f[n_] := Length@ Select[2n - Prime@ Range@ PrimePi@ n, PrimeQ]; nn = 100; t = Table[0, {nn}]; k = 1; cnt = 0; While[cnt < nn, a = f@k; If[a <= nn && t[[a]] == 0, t[[a]] = 2 k; cnt++]; k++]; t (* Robert G. Wilson v *)

CROSSREFS

Cf. A045917, A000954.

Sequence in context: A179116 A036954 A109679 * A005306 A075898 A091618

Adjacent sequences:  A023033 A023034 A023035 * A023037 A023038 A023039

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified April 20 13:52 EDT 2014. Contains 240806 sequences.