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a(n) is the largest number such that when written in base n, for each possible k, the number having the first k digits of a(n) is divisible by k.
5

%I #13 Oct 19 2017 03:14:42

%S 2,510,10801,8002800,328224963,543132112659030,1625617313969282,

%T 976950495904635536636,3608528850368400786036725,

%U 633984966211379026884314402,830642837707972528309709136652,311178293035966860075741106050464008245,418859156568815767928583230192107024079856024

%N a(n) is the largest number such that when written in base n, for each possible k, the number having the first k digits of a(n) is divisible by k.

%C This is not monotonic: a(14) > a(15).

%H Karl W. Heuer, <a href="/A109032/b109032.txt">Table of n, a(n) for n = 2..32</a>

%H MathStackExchange, <a href="http://math.stackexchange.com/questions/411897/find-the-largest-number-having-this-property">Find the largest number having this property</a>, Jan 2013.

%H A. Mihailovs, <a href="http://beta.mapleprimes.com/blog/alec/ponder_this">Ponder This</a>.

%H smit0399, <a href="http://home.kpn.nl/smit0399/3608528850368400786036725.htm">veeldeelbaarheid</a> (in Dutch).

%Y Cf. A109783.

%K nonn,base

%O 2,1

%A _Don Reble_, Aug 17 2005

%E a(13)-a(32) from _Karl W. Heuer_, Jan 08 2015