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%I #22 Apr 17 2022 11:10:42
%S 29,30,32,35,39,44,50,57,58,61,63,65,72,74,76,84,87,88,89,91,92,94,95,
%T 97,99,102,107,109,113,116,118,120,122,123,125,126,127,134,138,144,
%U 145,146,147,148,149,150,153,154,156,157,163,164,165,166,169,174,175,179,180,182,183,191,194,196,200
%N Numbers k such that 2*k^2 + 29 is semiprime.
%C The least positive k for which 2*k^2 + 29 is neither prime nor semiprime is k = 185, which gives 2*k^2 + 29 = 68479 = 31*47^2.
%e a(5) = 39; 2*39^2 + 29 = 3071 = 37*83 is semiprime.
%t Select[Range[200], PrimeOmega[2*#^2 + 29] == 2 &] (* _Amiram Eldar_, Apr 15 2022 *)
%o (Python)
%o from sympy import primeomega
%o def semiprime(n): return primeomega(n) == 2
%o print([k for k in range(140) if semiprime(2*k**2+29)]) # _Michael S. Branicky_, Apr 15 2022
%o (PARI) isok(k) = bigomega(2*k^2+29) == 2; \\ _Michel Marcus_, Apr 15 2022
%Y Subsequence of A007642, whose first term not in this sequence is 185.
%Y Cf. A241554, A352949, A353388.
%K nonn
%O 1,1
%A _Rémi Guillaume_, Apr 15 2022