

A214532


List of words over {1,9} with equal numbers of 1's and 9's.


0



19, 91, 1199, 1919, 1991, 9119, 9191, 9911, 111999, 119199, 119919, 119991, 191199, 191919, 191991, 199119, 199191, 199911, 911199, 911919, 911991, 919119, 919191, 919911, 991119, 991191, 991911, 999111, 11119999, 11191999
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OFFSET

1,1


COMMENTS

This is to 9 as A214531 is to 8, as A214530 is to 7, as A214530 is to 6, as A214522 is to 5, as A214521 is to 4, as A214488 is to 3, and as A214218 is to 2.
The subsequence of primes (when interpreted as decimal integers) is A087515.


LINKS

Table of n, a(n) for n=1..30.


MATHEMATICA

FromDigits/@(Flatten[Permutations/@Table[Join[Table[1, {n}], Table[9, {n}]], {n, 4}], 1]) (* Harvey P. Dale, Aug 20 2014 *)


CROSSREFS

Cf. A214218, A214488, A214521, A214522, A214524, A214530, A214531.
Sequence in context: A043232 A044012 A288485 * A118294 A157098 A037238
Adjacent sequences: A214529 A214530 A214531 * A214533 A214534 A214535


KEYWORD

nonn,base,easy


AUTHOR

Jonathan Vos Post, Jul 20 2012


STATUS

approved



