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A353388
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Numbers k such that 2*k^2 + 29 is neither a prime nor a semiprime.
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3
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185, 187, 232, 247, 261, 309, 311, 370, 371, 373, 435, 442, 464, 479, 501, 516, 520, 553, 557, 561, 590, 614, 619, 620, 621, 627, 638, 667, 701, 702, 705, 708, 714, 738, 755, 769, 796, 797, 802, 812, 836, 849, 853, 856, 869, 874, 890, 896, 899, 903, 906, 915, 943, 957, 960, 964, 973, 990
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OFFSET
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1,1
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COMMENTS
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If k is a term, then so is k + j*(2*k^2+29) for all natural numbers j. - Robert Israel, Jul 23 2023
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LINKS
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MAPLE
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select(k -> numtheory:-bigomega(2*k^2+29) > 2, [$1..1000]); # Robert Israel, Jul 23 2023
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MATHEMATICA
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Select[Range[1000], PrimeOmega[2*#^2 + 29] >= 3 &] (* Amiram Eldar, Apr 17 2022 *)
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PROG
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(PARI) for(k=0, 1000, if(bigomega(2*k^2+29) >= 3, print1(k, ", ")))
(Python)
from sympy import primeomega
def ok(n): return primeomega(2*n**2 + 29) >= 3
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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