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 A275023 Cubes c such that c + 2 and c - 2 are semiprime. 1
 8, 216, 1331, 2197, 4913, 9261, 15625, 35937, 59319, 68921, 117649, 185193, 421875, 531441, 658503, 704969, 1030301, 1367631, 3723875, 5268024, 5359375, 11390625, 13651919, 16581375, 17779581, 19902511, 23149125, 25672375, 29503629, 36264691, 38958219, 40353607 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A000578 and A105571. LINKS K. D. Bajpai, Table of n, a(n) for n = 1..10000 EXAMPLE a(1) = 8 = 2^3. Also, 8 + 2 = 10 = 2*5; 8 - 2 = 6 = 2*3; both are semiprime. a(2) = 216 = 6^3. Also, 216 + 2 = 218 = 2*109; 216 - 2 = 214 = 2*107; both are semiprime. MATHEMATICA Select[Table[n^3, {n, 1000}], PrimeOmega[# + 2] == 2 && PrimeOmega[# - 2] == 2 &] PROG (PARI) for (n = 1, 1000, s = n^3; if(bigomega (s+2) == 2 && bigomega (s-2) == 2, print1 (s, ", "))) CROSSREFS Cf. A000578, A001358, A105571, A278022. Sequence in context: A072159 A016827 A239222 * A163289 A060459 A007409 Adjacent sequences:  A275020 A275021 A275022 * A275024 A275025 A275026 KEYWORD nonn AUTHOR K. D. Bajpai, Nov 12 2016 STATUS approved

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Last modified July 29 04:42 EDT 2021. Contains 346340 sequences. (Running on oeis4.)