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%I #7 Mar 24 2017 00:47:55
%S 0,0,1,0,2,2,3,2,3,2,4,3,6,4,5,3,7,2,7,5,7,6,7,4,9,7,6,5,8,5,10,4,8,8,
%T 7,5,13,8,8,6,12,7,12,7,8,11,11,5,13,9,12,9,11,5,13,11,13,12,12,5,17,
%U 11,11,8,13,9,14,9,12,7,14,8,18,11,9,11,13,11
%N a(n) gives the number of bases, b>1, in which n is an early bird.
%C A number n is called an early bird in base b, if its digits in base b appear in the concatenation of the digits in base b of the numbers from 1 to n-1.
%H Paul Tek, <a href="/A229123/b229123.txt">Table of n, a(n) for n = 1..10000</a>
%H Paul Tek, <a href="/A229123/a229123.txt">C program for this sequence</a>
%H Paul Tek, <a href="/A229123/a229123.png">Illustration of the bases in which n is an early bird, where n ranges from 1 to 1000</a>
%e The number 1 is never an early bird, so a(1)=0.
%e The number 3 is an early bird only in base 2, so a(3)=1.
%e The number 7 is an early bird in bases 2, 3 and 5, so a(7)=3.
%o (C) See Link section.
%Y Cf. A116700, A161373, A135549.
%K nonn,base
%O 1,5
%A _Paul Tek_, Sep 14 2013