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A345016 Positive even integers with an odd number of Goldbach partitions. 1
4, 6, 8, 12, 22, 24, 26, 30, 40, 44, 48, 52, 54, 56, 62, 64, 70, 74, 76, 78, 82, 86, 90, 94, 96, 98, 104, 112, 124, 128, 130, 132, 136, 140, 144, 148, 156, 158, 164, 168, 170, 174, 176, 178, 186, 188, 192, 194, 196, 198, 202, 206, 208, 210, 216, 218, 220, 222, 224, 226, 230 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Goldbach Partition
EXAMPLE
24 is in the sequence since it is a positive even integer with an odd number of Goldbach partitions: (19,5), (17,7), and (13,11).
MATHEMATICA
Table[If[Mod[Sum[(PrimePi[k] - PrimePi[k - 1]) (PrimePi[2 n - k] - PrimePi[2 n - k - 1]), {k, n}] + 1, 2] == 0, 2 n, {}], {n, 200}] // Flatten
CROSSREFS
Sequence in context: A323059 A136254 A146528 * A216051 A176777 A318761
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jun 05 2021
STATUS
approved

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Last modified May 22 20:45 EDT 2024. Contains 372758 sequences. (Running on oeis4.)