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 A162558 a(n) = ((3+sqrt(3))*(5+sqrt(3))^n + (3-sqrt(3))*(5-sqrt(3))^n)/6. 2
 1, 6, 38, 248, 1644, 10984, 73672, 495072, 3329936, 22407776, 150819168, 1015220608, 6834184384, 46006990464, 309717848192, 2085024691712, 14036454256896, 94493999351296, 636137999861248, 4282512012883968 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Fifth binomial transform of A108411. Binomial transform of A162557. Inverse binomial transform of A162757. 2nd binomial transform of A086405. - R. J. Mathar, Jul 17 2009 LINKS FORMULA a(n) = 10*a(n-1) - 22*a(n-2) for n > 1; a(0) = 1, a(1) = 6. G.f.: (1-4*x)/(1-10*x+22*x^2). From R. J. Mathar, Jul 17 2009: (Start) a(n) = 10*a(n-2) - 22*a(n-2). G.f.: (1-4*x)/(1-10*x+22*x^2). (End) PROG (MAGMA) Z:=PolynomialRing(Integers()); N:=NumberField(x^2-3); S:=[ ((3+r)*(5+r)^n+(3-r)*(5-r)^n)/6: n in [0..19] ]; [ Integers()!S[j]: j in [1..#S] ]; // Klaus Brockhaus, Jul 13 2009 CROSSREFS Cf. A108411 (powers of 3 repeated), A162557, A162757. Sequence in context: A180030 A135030 A217633 * A215466 A147957 A098410 Adjacent sequences:  A162555 A162556 A162557 * A162559 A162560 A162561 KEYWORD nonn AUTHOR Al Hakanson (hawkuu(AT)gmail.com), Jul 06 2009 EXTENSIONS Edited and extended beyond a(5) by Klaus Brockhaus, Jul 13 2009 More terms from R. J. Mathar, Jul 17 2009 STATUS approved

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Last modified March 21 22:19 EDT 2019. Contains 321382 sequences. (Running on oeis4.)