A013814 a(n) = 21^(4*n + 1).

21, 4084101, 794280046581, 154472377739119461, 30041942495081691894741, 5842587018385982521381124421, 1136272165922724266740722458520501, 220983347100817338120002444455525554981, 42977062327514056734916195400155065458259861

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..100

Tanya Khovanova, Recursive Sequences

Index entries for linear recurrences with constant coefficients, signature (194481).

Prog

(Magma) [21^(4*n+1): n in [0..15]]; // Vincenzo Librandi, Jul 07 2011
(Maxima) makelist(21^(4*n+1), n, 0, 20); /* Martin Ettl, Oct 21 2012 */
(PARI) a(n) = 21^(4*n+1); \\ Altug Alkan, Sep 08 2018

Crossrefs

Sequence in context: A173518 A033636 A138080 * A013898 A180727 A250487

Adjacent sequences: A013811 A013812 A013813 * A013815 A013816 A013817

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved