A109940 Largest k-digit multiple of n where k is the number of digits in n.

9, 8, 9, 8, 5, 6, 7, 8, 9, 90, 99, 96, 91, 98, 90, 96, 85, 90, 95, 80, 84, 88, 92, 96, 75, 78, 81, 84, 87, 90, 93, 96, 99, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Formula

a(n) = n * A097326(n). - Rémy Sigrist, Nov 01 2024

Mathematica

Table[Quotient[10^IntegerLength[n]-1, n]n, {n, 60}] (* Harvey P. Dale, Oct 16 2011 *)

Prog

(PARI) a(n) = n * ((10^#digits(n)-1)\n) \\ Rémy Sigrist, Nov 01 2024

Crossrefs

Cf. A097326.

Sequence in context: A309642 A146484 A116695 * A275106 A010549 A266554

Adjacent sequences: A109937 A109938 A109939 * A109941 A109942 A109943

Keyword

base,easy,nonn

Author

Amarnath Murthy, Jul 19 2005

Status

approved