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"Early Bird" numbers n such that n-1 is not an Early Bird (cf. A116700).
4

%I #4 Mar 30 2012 18:34:45

%S 12,21,23,31,34,41,45,51,56,61,67,71,78,81,89,91,101,110,121,131,141,

%T 151,161,171,181,191,201,210,231,241,251,261,271,281,291,301,310,341,

%U 351,361,371,381,391,401,410,451,461,471,481,491,501,510,561,571,581

%N "Early Bird" numbers n such that n-1 is not an Early Bird (cf. A116700).

%C Punctual Birds (A131881) are all numbers k with A132131(n) <= k < A132132(n) for some n Early Birds (A116700) are all numbers k with A132132(n) <= k < A132131(n+1) for some n

%H Graeme McRae, <a href="/A132132/b132132.txt">Table of n, a(n) for n = 1..27348</a>

%e a(1)=12 because 12 is the first Early Bird.

%e a(2)=21 because 21 is the second Early Bird.

%e a(3)=23 because 23 is the third Early Bird.

%e a(4)=31 because 31 is the fourth Early Bird.

%e a(5)=34 because 31-32 are Early Birds and 33 is not an Early Bird.

%Y Cf. A033307, A117804, A116700, A131881, A132131, A132133.

%K base,nonn

%O 1,1

%A _Graeme McRae_, Aug 11 2007