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 A079042 Numbers n in which the first k digits of n form an integer divisible by k^2, for k = 1, 2, ..., m, where m is the number of digits in n. 4

%I

%S 1,2,3,4,5,6,7,8,9,12,16,20,24,28,32,36,40,44,48,52,56,60,64,68,72,76,

%T 80,84,88,92,96,126,162,207,243,288,324,360,369,405,441,486,522,567,

%U 603,648,684,720,729,765,801,846,882,927,963,1264,2432,2880,3248,3600,3696

%N Numbers n in which the first k digits of n form an integer divisible by k^2, for k = 1, 2, ..., m, where m is the number of digits in n.

%e a(86) = 6480005 because 6 is divisible by 1^2, 64 by 2^2, 648 by 3^2, 6480 by 4^2, 64800 by 5^2, 648000 by 6^2, 6480005 by 7^2.

%Y Cf. A079041.

%K easy,fini,full,nonn,base

%O 1,2

%A Sudipta Das (juitech(AT)vsnl.net), Feb 01 2003

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Last modified December 3 20:09 EST 2021. Contains 349468 sequences. (Running on oeis4.)