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 A282671 Twice composite numbers. 0
 8, 12, 16, 18, 20, 24, 28, 30, 32, 36, 40, 42, 44, 48, 50, 52, 54, 56, 60, 64, 66, 68, 70, 72, 76, 78, 80, 84, 88, 90, 92, 96, 98, 100, 102, 104, 108, 110, 112, 114, 116, 120, 124, 126, 128, 130, 132, 136, 138, 140, 144, 148, 150, 152, 154, 156, 160, 162, 164, 168, 170, 172, 174 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Even numbers greater than 2 that do not appear in A001747. LINKS FORMULA a(n) = 2*A002808(n). - R. J. Mathar, Feb 23 2017 a(n) = A139270(n+1). - R. J. Mathar, Feb 25 2017 PROG (PARI) is(n)=n%2==0 && n>6 && !isprime(n/2) \\ Charles R Greathouse IV, Feb 21 2017 CROSSREFS Cf. A001747, A139270, A176100. Sequence in context: A166083 A326111 A091375 * A192991 A083348 A174261 Adjacent sequences:  A282668 A282669 A282670 * A282672 A282673 A282674 KEYWORD nonn,easy AUTHOR Alessandro Polcini, Feb 20 2017 STATUS approved

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Last modified September 20 10:51 EDT 2021. Contains 347584 sequences. (Running on oeis4.)