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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
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
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
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 06 2003
EXTENSIONS
More terms from Gabriel Cunningham (gcasey(AT)mit.edu), Sep 18 2003
STATUS
approved