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A216047 Consider the ordered Goldbach partitions of the even numbers m. Then a(n) is the least m which contains prime(n) such partitions composed of odd primes. 2
8, 10, 22, 34, 106, 178, 202, 358, 386, 502, 802, 694, 1322, 958, 1198, 1366, 1546, 1654, 2066, 2578, 2402, 2446, 2722, 2894, 2974, 3866, 3646, 3986, 4054, 4162, 4954, 5714, 5182, 6082, 6334, 6598, 6614, 6742, 7402, 8158, 7846, 8782, 8566, 9274, 9382, 9502 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A002372(a(n)/2) = p.

LINKS

J. Stauduhar and Donovan Johnson, Table of n, a(n) for n = 1..1000 (first 100 terms from J. Stauduhar)

EXAMPLE

With n = 1:  prime(1) = 2, so we want the least m that has 2 such partitions.  For m = 4, 4 = {2+2}, but 2 is not an odd prime number.  For m = 6, 6 has one such partition, {3+3}, but 1 is not a prime number.  For m = 8, 8 has two such partitions, {3+5, 5+3}, so a(1) = 8.

a(3) = 22: With n = 3, prime(3) = 5 and 22 = {3+19, 5+17, 11+11, 17+5, 19+3}.

MATHEMATICA

nn = 10^4; ps = Boole[PrimeQ[Range[1, 2*nn, 2]]]; lst = Table[Sum[ps[[i]] ps[[n - i + 1]], {i, n}], {n, nn}]; t = {}; p = 0; While[p = NextPrime[p]; pos = Position[lst, p, 1, 1]; pos != {}, AppendTo[t, 2*pos[[1, 1]]]]; t (* T. D. Noe, Aug 31 2012 *)

CROSSREFS

Cf. A002372.

Sequence in context: A338820 A302429 A292999 * A032488 A102844 A303199

Adjacent sequences:  A216044 A216045 A216046 * A216048 A216049 A216050

KEYWORD

nonn

AUTHOR

J. Stauduhar, Aug 30 2012

STATUS

approved

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Last modified November 26 01:22 EST 2020. Contains 338631 sequences. (Running on oeis4.)