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A216050 Consider the unordered Goldbach partitions of the even numbers m. Then a(n) is the least m which contains 2n-1 such partitions composed of odd primes. 1
6, 22, 48, 78, 90, 144, 168, 234, 288, 210, 300, 474, 528, 390, 480, 570, 672, 756, 714, 690, 630, 930, 960, 924, 1134, 840, 1302, 1230, 1050, 1386, 1380, 1896, 1620, 1500, 1530, 1590, 1470, 1800, 2244, 2160, 1920, 1680, 2040, 2478, 2838, 1890, 2460, 2580 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A002375(a(n)/2) = 2n-1.
LINKS
EXAMPLE
a(1) = 6, because 6 = {3+3} is the least m to contain one such partition.
a(2) = 22, because 22 = {3+19, 5+17, 11+11} is the least m to contain three such partitions.
a(3) = 48, because 48 = {5+43, 7+41, 11+37, 17+31, 19+29} is the least m to contain five such partitions.
MATHEMATICA
For[ls1=ls2={}; ct1=n=1, n<=1000, n++, For[ct2=i=1, i<=2n-1, i++, If[OddQ[i] && PrimeQ[i] && PrimeQ[2n-i], ct2++]]; AppendTo[ls1, Floor[ct2/2]]; While[(pos=Position[ls1, ct1, 1, 1])!={}, AppendTo[ls2, 2*pos[[1, 1]]]; ct1+=2; ]]; ls2 (* J. Stauduhar, Sep 04 2012 *)
CROSSREFS
Cf. A002375.
Sequence in context: A015721 A182200 A072972 * A202803 A092185 A216894
KEYWORD
nonn
AUTHOR
J. Stauduhar, Sep 04 2012
STATUS
approved

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Last modified June 2 01:36 EDT 2023. Contains 363078 sequences. (Running on oeis4.)