A319358 a(n) = (10^n - 1)^9.

0, 387420489, 913517247483640899, 991035916125874083964008999, 999100359916012598740083996400089999, 999910003599916001259987400083999640000899999, 999991000035999916000125999874000083999964000008999999

Offset: 0

Author

Seiichi Manyama, Sep 17 2018

Keywords

• nonn

Comments

Number of 9 in a(n) is 5*n-8 for n > 2.

Examples

			n|   a(n) can be divided into 9 parts for n > 3.
-+------------------------------------------------------
3|   99   1035   9   16125      874083   9   64008   999
4|  999  10035  99  160125  9  8740083  99  640008  9999
5| 9999 100035 999 1600125 99 87400083 999 6400008 99999
		

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..100
• Index entries for linear recurrences with constant coefficients, signature (1111111111, -112233445443322110, 1123457901110987543211000, -1123570145779775409653211000000, 112358025801220975197532110000000000, -1123570145779775409653211000000000000000, 1123457901110987543211000000000000000000000, -112233445443322110000000000000000000000000000, 1111111111000000000000000000000000000000000000, -1000000000000000000000000000000000000000000000).

Crossrefs

Cf. A001017, A002283, A059988, A272067, A272068.

Programs

Mathematica

a[n_]:=(10^n - 1)^9 ; Array[a,  50, 0] (* Stefano Spezia, Sep 17 2018 *)

PARI

a(n) = (10^n-1)^9;

Formula

a(n) = A002283(n)^9.