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 A180082 Semiprime centered cube numbers: m^3 + (m+1)^3. 3
 9, 35, 91, 341, 559, 1241, 6119, 7471, 17261, 19909, 75241, 143009, 257651, 323839, 671509, 860851, 967591, 1433969, 1482571, 1970299, 2348641, 2772559, 3413159, 4548059, 5313691, 5666509, 7233841, 7520291, 9568441 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are no prime centered cube numbers because m^3+(m+1)^3=(2m+1)(m^2+m+1). - Zak Seidov, Feb 08 2011 Products of two primes p and q = (p^2+3)/4 with p's in A118939. - Zak Seidov, Feb 08 2011 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 FORMULA A001358 INTERSECTION A005898. EXAMPLE a(1) = 1^3 + (1+1)^3 = 9 = 3^2 is semiprime. a(2) = 2^3 + (2+1)^3 = 35 = 5 * 7. a(3) = 3^3 + (3+1)^3 = 91 = 7 * 13. MATHEMATICA Select[Total/@Partition[Range[200]^3, 2, 1], PrimeOmega[#]==2&] (* Harvey P. Dale, Feb 02 2019 *) CROSSREFS Cf. A001222, A001358, A005898. Sequence in context: A212100 A005898 A034957 * A002418 A118414 A279218 Adjacent sequences:  A180079 A180080 A180081 * A180083 A180084 A180085 KEYWORD nonn,easy AUTHOR Jonathan Vos Post, Feb 06 2011 EXTENSIONS More terms from Vincenzo Librandi, Feb 06 2011 STATUS approved

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Last modified January 23 19:45 EST 2020. Contains 331175 sequences. (Running on oeis4.)