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 A161731 Expansion of (1-3*x)/(1-8*x+14*x^2). 6
 1, 5, 26, 138, 740, 3988, 21544, 116520, 630544, 3413072, 18476960, 100032672, 541583936, 2932214080, 15875537536, 85953303168, 465368899840, 2519604954368, 13641675037184, 73858930936320, 399887996969984 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Fourth binomial transform of A016116. Inverse binomial transform of A161734. Binomial transform of A086351. - R. J. Mathar, Jun 18 2009 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (8,-14). FORMULA a(n) = ((2+sqrt(2))*(4+sqrt(2))^n+(2-sqrt(2))*(4-sqrt(2))^n)/4. a(n)=8*a(n-1)-14*a(n-2). - R. J. Mathar, Jun 18 2009 a(n) = A081180(n+1) -3*A081180(n). - R. J. Mathar, Jul 19 2012 PROG (PARI) F=nfinit(x^2-2); for(n=0, 20, print1(nfeltdiv(F, ((2+x)*(4+x)^n+(2-x)*(4-x)^n), 4)[1], ", ")) \\ Klaus Brockhaus, Jun 19 2009 (MAGMA)[Floor(((2+Sqrt(2))*(4+Sqrt(2))^n+(2-Sqrt(2))*(4-Sqrt(2))^n)/4): n in [0..30]]; // Vincenzo Librandi, Aug 18 2011 CROSSREFS Cf. A016116, A086351, A161734. Sequence in context: A083331 A076025 A288785 * A049607 A035029 A081569 Adjacent sequences:  A161728 A161729 A161730 * A161732 A161733 A161734 KEYWORD nonn,easy AUTHOR Al Hakanson (hawkuu(AT)gmail.com), Jun 17 2009 EXTENSIONS Extended by R. J. Mathar and Klaus Brockhaus, Jun 18 2009 Edited by Klaus Brockhaus, Jul 05 2009 STATUS approved

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Last modified April 14 19:29 EDT 2021. Contains 342951 sequences. (Running on oeis4.)