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 A231960 Powers of 3 together with multiples of 6. 0
 1, 3, 6, 9, 12, 18, 24, 27, 30, 36, 42, 48, 54, 60, 66, 72, 78, 81, 84, 90, 96, 102, 108, 114, 120, 126, 132, 138, 144, 150, 156, 162, 168, 174, 180, 186, 192, 198, 204, 210, 216, 222, 228, 234, 240, 243, 246, 252, 258 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Union of A000244 and A008588 (without 0). Also, 1 and 3*(even numbers (A005843) UNION powers of 3 (A008588)). Also, numbers m such that m divides A057083(m-1), see the Smyth reference. LINKS C. Smyth, The Terms in Lucas Sequences Divisible by their Indices, Journal of Integer Sequences, Vol.13 (2010), Article 10.2.4. PROG (Sage) def is_in_A231960(n):     return 6.divides(n) or n==3^valuation(n, 3) CROSSREFS Cf. A029744. Sequence in context: A253277 A310155 A310156 * A052287 A156997 A063996 Adjacent sequences:  A231957 A231958 A231959 * A231961 A231962 A231963 KEYWORD nonn AUTHOR Thomas M. Bridge, Nov 15 2013 EXTENSIONS Edited by Ralf Stephan, Feb 28 2014 STATUS approved

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Last modified December 6 16:24 EST 2019. Contains 329808 sequences. (Running on oeis4.)