A013778 a(n) = 3^(4*n + 1).

3, 243, 19683, 1594323, 129140163, 10460353203, 847288609443, 68630377364883, 5559060566555523, 450283905890997363, 36472996377170786403, 2954312706550833698643, 239299329230617529590083, 19383245667680019896796723

Offset

0,1

Comments

Equivalently, powers of 3 with final digit 3. - Muniru A Asiru, Feb 06 2019

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Tanya Khovanova, Recursive Sequences

Index entries for linear recurrences with constant coefficients, signature (81).

Formula

From Philippe Deléham, Nov 25 2008: (Start)

a(n) = 81*a(n-1); a(0)=3.

G.f.: 3/(1-81*x). (End)

Maple

seq(coeff(series(3/(1-81*x), x, n+1), x, n), n = 0 .. 15); # Muniru A Asiru, Feb 06 2019

Mathematica

3^(1 + 4Range[0, 15]) (* Harvey P. Dale, Jan 31 2011 *)
NestList[81#&, 3, 20] (* Harvey P. Dale, Feb 26 2023 *)

Prog

(Magma) [3^(4*n+1): n in [0..20]]; // Vincenzo Librandi, Jun 27 2011
(Maxima) makelist(3^(4*n+1), n, 0, 20); /* Martin Ettl, Oct 21 2012 */
(GAP) List([0..15], n->3^(4*n+1)); # Muniru A Asiru, Feb 06 2019

Crossrefs

Sequence in context: A324444 A236249 A338453 * A146313 A092799 A229690

Adjacent sequences: A013775 A013776 A013777 * A013779 A013780 A013781

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved