cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A229123 a(n) gives the number of bases, b>1, in which n is an early bird.

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