The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A178935 a(n) = floor((3*4^n - 2*3^n)/5). 3
 0, 1, 6, 27, 121, 517, 2166, 8955, 36697, 149413, 605526, 2445723, 9853753, 39627589, 159148086, 638505531, 2559761689, 10256265445, 41076717846, 164461839579, 658312262905, 2634643765381, 10542759202806, 42183589235067, 168772014211801, 675201028661797 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 FORMULA G.f.: x*(1 - x - 3*x^2 + 4*x^3 - 7*x^4)/(1 - 7*x + 12*x^2 - x^4 + 7*x^5 - 12*x^6) = x*(1 - x - 3*x^2 + 4*x^3 - 7*x^4)/((1-3*x)*(1-4*x)*(1-x^4)). Recurrence: a(n+6) = 7*a(n+5) - 12*a(n+4) + a(n+2) - 7*a(n+1) + 12*a(n). PROG (Maxima) makelist(floor((3*4^n-2*3^n)/5) , n, 0, 12); (MAGMA) [Floor((3*4^n-2*3^n)/5): n in [0..30]]; // Vincenzo Librandi, Sep 06 2011 CROSSREFS Cf. A178934, A178936. Sequence in context: A080627 A079762 A175716 * A249792 A002912 A030297 Adjacent sequences:  A178932 A178933 A178934 * A178936 A178937 A178938 KEYWORD nonn,easy AUTHOR Emanuele Munarini, Dec 30 2010 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 2 23:09 EST 2020. Contains 338898 sequences. (Running on oeis4.)