A099675 Partial sums of repdigits of A002282.

8, 96, 984, 9872, 98760, 987648, 9876536, 98765424, 987654312, 9876543200, 98765432088, 987654320976, 9876543209864, 98765432098752, 987654320987640, 9876543209876528, 98765432098765416, 987654320987654304

Offset

1,1

Links

Table of n, a(n) for n=1..18.

Index entries for linear recurrences with constant coefficients, signature (12,-21,10).

Formula

a(n) = (8/81)*(10^(n+1) - 9*n - 10). - R. Piyo (nagoya314(AT)yahoo.com), Dec 10 2004

a(n) = 12*a(n-1) - 21*a(n-2) + 10*a(n-3). - Wesley Ivan Hurt, Jan 20 2024

Example

8 + 88 + 888 + 8888 + 88888 = a(5) = 98760.

Mathematica

<<NumberTheory`NumberTheoryFunctions` Table[{k, Table[Apply[Plus, Table[k*(10^n-1)/9, {n, 1, m}]], {m, 1, 35}]}, {k, 1, 9}]
Table[8/9*Sum[10^i - 1, {i, n}], {n, 18}] (* Robert G. Wilson v, Nov 20 2004 *)

Crossrefs

Cf. A057932, A002275-A002283, A099669-A099675.

Sequence in context: A069650 A066424 A276593 * A211345 A060458 A173834

Adjacent sequences: A099672 A099673 A099674 * A099676 A099677 A099678

Keyword

base,nonn

Author

Labos Elemer, Nov 17 2004

Status

approved