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Smallest number beginning with n and having n different prime divisors (which may be repeated).
1

%I #13 Mar 22 2014 05:27:50

%S 11,20,30,420,5460,60060,746130,80059980,900029130,10407767370,

%T 1100869379610,12026713528830,1300912477633230,14299762385778870,

%U 1502172599891453490,160000041334479776430,17000158733027932351890

%N Smallest number beginning with n and having n different prime divisors (which may be repeated).

%e a(1)=11 because it begins with 1 and has one prime divisor. a(5)=5460=2^2*3*5*7*13 has 5 distinct prime divisors.

%Y Cf. A077522.

%K base,nonn

%O 1,1

%A Mark Hudson (mrmarkhudson(AT)hotmail.com), Feb 11 2003

%E More terms from _Erich Friedman_, Aug 08 2005

%E a(11) was incorrect. _Franklin T. Adams-Watters_ found a smaller candidate, 1102786855170 and asks if this is the true value of a(11). Dec 07 2006

%E a(11)-a(17) from _Donovan Johnson_, Sep 03 2008