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Number of Niven numbers <= 10^n.
4

%I #34 Dec 23 2015 23:09:30

%S 10,33,213,1538,11872,95428,806095,6954793,61574510,553007106,

%T 5024332415,45975917532,422675487735,3902487368735,36116199480944,

%U 335270244411437,3128167760734131,29410615796612778,278977554117741592,2664295247105153610,25539536718894979516

%N Number of Niven numbers <= 10^n.

%D J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 213, pp 62, Ellipses, Paris 2008.

%H Hiroaki Yamanouchi, <a href="/A140866/b140866.txt">Table of n, a(n) for n = 1..100</a>

%H J.-M. DeKoninck, N. Doyon, <a href="http://www.fq.math.ca/Scanned/41-5/dekoninck.pdf">On the number of Niven numbers up to x</a>, Fib. Quart. 41 (5) (2003) 431

%H Hiroaki Yamanouchi, <a href="/A140866/a140866.py.txt">Python code</a>

%F a(n) = A086706(10^n).

%Y Cf. A005349, A086706.

%K nonn,base

%O 1,1

%A _Lekraj Beedassy_, Jul 20 2008

%E a(10)-a(12) from _Donovan Johnson_, Mar 10 2010

%E a(13)-a(21) from _Hiroaki Yamanouchi_, Mar 08 2014