A087343 Smallest k such that the concatenation of the n numbers k, k-1, k-2, k-3,... k-n+1 (the concatenation of n successive numbers in descending order) is divisible by n, or 0 if no such number exists.

1, 3, 3, 5, 9, 7, 22, 9, 9, 19, 20, 13, 19, 29, 19, 27, 28, 19, 19, 39, 23, 31, 33, 25, 49, 57, 27, 43, 46, 39, 57, 43, 42, 45, 64, 37, 77, 81, 46, 59, 41, 51, 53, 55, 49, 79, 66, 59, 99, 99, 62, 83, 68, 55, 64, 99, 81, 75, 90, 79, 106, 109, 65, 75, 139, 75, 154, 79, 79, 99

Offset

1,2

Links

Table of n, a(n) for n=1..70.

Example

a(7) = 22 as 22212019181716 is the concatenation of 22,21,20,19,18,17 and 16 and is divisible by 7.

Crossrefs

Cf. A087342.

Sequence in context: A073060 A183526 A337562 * A079586 A354953 A125960

Adjacent sequences: A087340 A087341 A087342 * A087344 A087345 A087346

Keyword

base,nonn

Author

Amarnath Murthy, Sep 06 2003

Extensions

More terms from Gabriel Cunningham (gcasey(AT)mit.edu), Sep 18 2003

Status

approved