A259925 a(n) = (n^2 - n - 1)^n.

1, -1, 1, 125, 14641, 2476099, 594823321, 194754273881, 83733937890625, 45848500718449031, 31181719929966183601, 25804264053054077850709, 25542038069936263923006961, 29806575070123343006591796875, 40504199006061377874300161158921

Offset: 0

Author

Ilya Gutkovskiy, Jul 09 2015

Keywords

• sign
• easy

Comments

(n^2-n-1) is the Fibonacci polynomial; so (n^2 - n - 1)^n = 0 has a single root phi (A001622).

Examples

			For n = 0, a(0) = (0^2 - 0 - 1)^0 = (-1)^0 = 1.
		

Crossrefs

Cf. A165900.

Programs

Magma

[(n^2 - n - 1)^n: n in [0..20]]; // Vincenzo Librandi, Jul 10 2015

Maple

A259925:=n->(n^2-n-1)^n: seq(A259925(n), n=0..20); # Wesley Ivan Hurt, Jul 10 2015

Mathematica

Table[(n^2 - n - 1)^n, {n, 0, 10}]

PARI

vector(20, n,  n--; (n^2 - n - 1)^n) \\ Michel Marcus, Aug 06 2015

Sage

[(n**2 - n - 1)**n for n in range(21)] # Anders Hellström, Jul 10 2015

Formula

a(n) = A165900(n)^n.

Extensions

More terms from Vincenzo Librandi, Jul 10 2015