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 A140429 a(n) = floor(3^(n-1)). 4
 0, 1, 3, 9, 27, 81, 243, 729, 2187, 6561, 19683, 59049, 177147, 531441, 1594323, 4782969, 14348907, 43046721, 129140163, 387420489, 1162261467, 3486784401, 10460353203, 31381059609, 94143178827, 282429536481, 847288609443 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Binomial transform of Jacobsthal numbers A001045. Implicit use in A094555 (Barry). LINKS Index entries for linear recurrences with constant coefficients, signature (3). FORMULA a(n) = floor(3^(n-1)) = A000244(n-1) = A133494(n), n >= 1. O.g.f.: x/(1-3x). - R. J. Mathar, Aug 27 2008 PROG (PARI) a(n)=if(n<2, n, 3^(n-1)) \\ Charles R Greathouse IV, Oct 03 2016 (PARI) a(n)=floor(3^(n-1)) \\ M. F. Hasler, Apr 13 2018 CROSSREFS Cf. A000079, A131577, A133494. Sequence in context: A216097 A243845 * A141413 A000244 A133494 A050733 Adjacent sequences:  A140426 A140427 A140428 * A140430 A140431 A140432 KEYWORD nonn,easy AUTHOR Paul Curtz, Jun 19 2008 EXTENSIONS Extended by R. J. Mathar, Aug 28 2008 New name by M. F. Hasler, Apr 13 2018 STATUS approved

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