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 A229123 a(n) gives the number of bases, b>1, in which n is an early bird. 1
 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, 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, 11, 11, 8, 13, 9, 14, 9, 12, 7, 14, 8, 18, 11, 9, 11, 13, 11 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS 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. LINKS Paul Tek, Table of n, a(n) for n = 1..10000 Paul Tek, C program for this sequence EXAMPLE The number 1 is never an early bird, so a(1)=0. The number 3 is an early bird only in base 2, so a(3)=1. The number 7 is an early bird in bases 2, 3 and 5, so a(7)=3. PROG (C) See Link section. CROSSREFS Cf. A116700, A161373, A135549. Sequence in context: A327161 A350067 A308450 * A173908 A329045 A329345 Adjacent sequences: A229120 A229121 A229122 * A229124 A229125 A229126 KEYWORD nonn,base AUTHOR Paul Tek, Sep 14 2013 STATUS approved

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Last modified March 22 01:15 EDT 2023. Contains 361413 sequences. (Running on oeis4.)