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!)
 A191641 a(n) = floor((1 + 4^n)/(1 + 4*n)). 2
 1, 1, 5, 15, 48, 163, 565, 1985, 7085, 25575, 93206, 342392, 1266205, 4709393, 17602325, 66076419, 248983611, 941362695, 3569842947, 13574217626, 51741723660, 197665011735, 756653163200, 2901803883615, 11147523830125, 42891425022576, 165269711096165 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA f[n_] := Floor[(1+4^n)/(1+4 n)] Table[f[n], {n, 1, 40}]     (* A191641 *) PROG (MAGMA) [Floor((1+4^n)/(1+4*n)): n in [1..30] ]; // Vincenzo Librandi, Sep 10 2011 (Maxima) A191641(n):=floor((1+4^n)/(1+4*n))\$ makelist(A191641(n), n, 1, 30); /* Martin Ettl, Oct 25 2012 */ CROSSREFS Cf. A191640, A191634, A191633. Sequence in context: A126944 A077841 A126945 * A199892 A152809 A034539 Adjacent sequences:  A191638 A191639 A191640 * A191642 A191643 A191644 KEYWORD nonn AUTHOR Clark Kimberling, Jun 09 2011 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 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)