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A078204
Smallest multiple of the concatenation of 1 up to n that begins with the concatenation of n down to 1.
1
1, 216, 32103, 4321468, 543217035, 65432173824, 7654321572835, 876543212074068, 98765432187654312, 109876543212580239340, 11109876543210457373921742, 12111098765432151566924849880
OFFSET
1,2
EXAMPLE
a(3) = 32103 = 123 * 261.
MATHEMATICA
f[n_] := Module[{upto = FromDigits[Range[n]], downfrom = FromDigits[Reverse[Range[n]]], i = 1}, While[upto - Mod[10^i downfrom, upto] > 10^i, i++ ]; 10^i downfrom + upto - Mod[10^i downfrom, upto]]; Table[f[n], {n, 2, 9}]
CROSSREFS
Cf. A078205.
Sequence in context: A269285 A133052 A365629 * A230466 A201248 A207553
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 22 2002
EXTENSIONS
More terms from Harvey P. Dale, Dec 07 2002
More terms from Sascha Kurz, Jan 04 2003
STATUS
approved