OFFSET
1,1
COMMENTS
Periodic with cycle of length 9: {3, 5, 3, 3, 2, 6, 3, 8, 9}.
a(n) also arises from the decimal expansion of 117775463/333333333 = 0.repeat(353326389).
LINKS
Eric Weisstein's World of Mathematics, Digital Root.
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 1).
FORMULA
EXAMPLE
For a(11) = 5 because 11+11^2+11^3 = 1463, and 1+4+6+3 = 14. Result is 5, which is the digital root of 14.
MATHEMATICA
PadRight[{}, 120, {3, 5, 3, 3, 2, 6, 3, 8, 9}] (* Vincenzo Librandi, Jul 18 2016 *)
PROG
(Magma) &cat [[3, 5, 3, 3, 2, 6, 3, 8, 9]^^10]; // Vincenzo Librandi, Jul 18 2016
CROSSREFS
KEYWORD
base,nonn,easy
AUTHOR
Peter M. Chema, Dec 07 2014
EXTENSIONS
Edited: name specified, digital root link added, a comment rewritten and moved to formula section. - Wolfdieter Lang, Jan 05 2015
STATUS
approved