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A342566
Noncube factors k > 0 such that k*x^3 + 1 produces a new minimum of its Hardy-Littlewood constant.
1
2, 3, 5, 7, 11, 13, 29, 43, 83, 239, 463, 911, 1483, 1721, 3067, 4187, 10613, 12433, 15287, 26447
OFFSET
1,1
COMMENTS
a(21)>40000.
For more information and references see A331950.
4187=53*79 is the first nonprime term.
EXAMPLE
n a(n) Hardy-Littlewood np / (expected number of primes)
constant (rounded) obtained from Li(a(n)*(10^9)^3+1)
np (x<=10^9) (similar to table in A331946)
1 2 2.597079115 43503785 2.69054
2 3 2.085815908 34707483 2.16060
3 5 1.428347905 23566489 1.47910
4 7 1.290763004 21179402 1.33641
5 11 1.241279598 20211462 1.28447
...
18 12433 0.450506688 6582602 0.46462
19 15287 0.422449638 6150009 0.43536
20 26447 0.418323708 6045844 0.43130
CROSSREFS
Cf. A331946 (similar for k*x^2+1), A331950, A342549.
Sequence in context: A181525 A082843 A162567 * A067908 A236128 A332341
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner, May 03 2021
STATUS
approved