OFFSET
0,1
COMMENTS
From Klaus Brockhaus, May 25 2010: (Start)
Continued fraction expansion of 2+sqrt(5).
Decimal expansion of 4/9.
Inverse binomial transform of A020707. (End)
LINKS
Tom Edgar, Proof without words: sum of powers of 4/9, Math. Mag. 89 no. 3 (2016) 191.
Tanya Khovanova, Recursive Sequences
INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 1012
Dominika Závacká, Cristina Dalfó, and Miquel Angel Fiol, Integer sequences from k-iterated line digraphs, CEUR: Proc. 24th Conf. Info. Tech. - Appl. and Theory (ITAT 2024) Vol 3792, 156-161. See p. 161, Table 2.
Index entries for linear recurrences with constant coefficients, signature (1).
FORMULA
From Klaus Brockhaus, May 25 2010: (Start)
a(n) = 4.
G.f.: 4/(1-x). (End)
E.g.f.: 4*e^x. - Vincenzo Librandi, Jan 29 2012
PROG
(PARI) a(n) = 4 \\ Charles R Greathouse IV, Apr 07 2012
(Maxima) makelist(4, n, 0, 30); /* Martin Ettl, Nov 09 2012 */
(Python)
def A010709(n): return 4 # Chai Wah Wu, Mar 22 2023
CROSSREFS
From Klaus Brockhaus, May 25 2010: (Start)
KEYWORD
AUTHOR
STATUS
approved