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A360740 Semiprimes of the form k^2 + 3. 1
4, 39, 259, 327, 403, 579, 679, 1027, 1159, 1299, 1603, 1939, 2119, 2307, 3139, 3603, 4359, 4627, 6087, 6403, 7747, 9607, 10003, 10407, 10819, 11667, 13459, 13927, 14403, 16387, 18499, 21907, 23107, 26899, 28903, 30279, 30979, 33127, 35347, 36103, 36867, 38419 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A242331 gives the corresponding values of k.
LINKS
FORMULA
a(n) = A242331(n)^2 + 3.
EXAMPLE
259 is a term because 16^2 + 3 = 259 = 7*37.
MATHEMATICA
Select[Range[0, 200]^2 + 3, PrimeOmega[#] == 2 &] (* Amiram Eldar, Feb 18 2023 *)
CROSSREFS
Sequence in context: A112460 A296594 A290559 * A059945 A198853 A093851
KEYWORD
nonn,easy
AUTHOR
Elmo R. Oliveira, Feb 18 2023
STATUS
approved

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Last modified March 29 01:36 EDT 2024. Contains 371264 sequences. (Running on oeis4.)