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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

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Last modified December 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)