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 A103396 Semiprimes in A103376. 2
 4, 9, 15, 21, 33, 38, 58, 65, 86, 106, 121, 129, 265, 511, 2038, 2059, 4097, 4174, 7894, 16021, 19857, 31313, 32419, 33238, 37711, 116197, 196609, 220937, 262978, 273926, 955743, 34826059, 64229819, 67835071, 77834009, 497049562, 4370946037 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A103376 with A001358. LINKS Table of n, a(n) for n=1..37. MATHEMATICA SemiprimeQ[n_] := Plus @@ FactorInteger[n][[All, 2]] == 2; k = 8; Do[a[n] = 1, {n, k + 1}]; a[n_] := a[n] = a[n - k] + a[n - k - 1]; Union[Select[Array[a, 280], SemiprimeQ]] Union[Select[LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1}, 300], PrimeOmega[#]==2&]] (* Harvey P. Dale, May 07 2015 *) CROSSREFS Cf. A001358, A103376, A103386, A103392-A103401. Sequence in context: A099055 A162801 A335250 * A103400 A103399 A103398 Adjacent sequences: A103393 A103394 A103395 * A103397 A103398 A103399 KEYWORD nonn,easy AUTHOR Jonathan Vos Post, Feb 05 2005 EXTENSIONS Edited and extended by Ray Chandler, Feb 10 2005 STATUS approved

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Last modified December 7 11:41 EST 2023. Contains 367656 sequences. (Running on oeis4.)