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A352169 Numbers k with a Goldbach partition (p,q) such that k/2 divides at least one of p*q +- 1. 0
8, 10, 12, 16, 20, 24, 30, 36, 40, 42, 48, 50, 52, 56, 58, 60, 64, 66, 70, 72, 74, 80, 84, 90, 96, 106, 112, 120, 128, 130, 132, 144, 156, 160, 168, 170, 176, 180, 184, 192, 198, 204, 210, 216, 220, 222, 224, 228, 232, 234, 240, 244, 246, 252, 260, 264, 276, 280, 288, 294, 296 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Goldbach Partition.
EXAMPLE
20 is in the sequence since it has a Goldbach partition, namely (3,17), such that 20/2 = 10 | 3*17-1 = 50.
PROG
(PARI) isok(k) = if (!(k%2), my(q); forprime(p=2, k, if (isprime(q=k-p), if (!((p*q-1) % (k/2)) || !((p*q+1) % (k/2)), return(1))))); \\ Michel Marcus, Mar 07 2022
CROSSREFS
Sequence in context: A154786 A335013 A249628 * A158273 A157939 A208154
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Mar 06 2022
STATUS
approved

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Last modified April 30 19:58 EDT 2024. Contains 372141 sequences. (Running on oeis4.)