1,6

Table of n, a(n) for n=1..81.

Moussa Benoumhani, A Sequence of Binomial Coefficients Related to Lucas and Fibonacci Numbers, J. Integer Seqs., Vol. 6, 2003, Article 03.2.1.

a(n) = ceiling(1/10*(5*n-4-sqrt(5*n^2-4))).

Table[Ceiling[1/10 (5 n - 4 - Sqrt[5 n^2 - 4])], {n, 1, 100}] (* Vincenzo Librandi, May 21 2015 *)

(PARI) vector(80, n, ceil(1/10*(5*n-4-sqrt(5*n^2-4)))) \\ Michel Marcus, May 20 2015

(MAGMA) [Ceiling(1/10*(5*n-4-Sqrt(5*n^2-4))): n in [1..100]]; // Vincenzo Librandi, May 21 2015

Sequence in context: A274024 A285189 A051889 * A217538 A333348 A194920

Adjacent sequences: A086704 A086705 A086706 * A086708 A086709 A086710

nonn

Benoit Cloitre, Jul 28 2003

approved