The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A214531 List of words over {1,8} with equal numbers of 1's and 8's. 2
 18, 81, 1188, 1818, 1881, 8118, 8181, 8811, 111888, 118188, 118818, 118881, 181188, 181818, 181881, 188118, 188181, 188811, 811188, 811818, 811881, 818118, 818181, 818811, 881118, 881181, 881811, 888111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This 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. All of these, interpreted as decimal integers are divisible by 9, because each pair of "1" and "8" contributes a digital sum of 9, hence the total is divisible by 9. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA With[{tb=Table[Join[PadRight[{}, n, 1], PadRight[{}, n, 8]], {n, 3}]}, FromDigits/@ Flatten[Permutations/@tb, 1]] (* Harvey P. Dale, Jan 17 2014 *) CROSSREFS Cf. A214218, A214488, A214521, A214522, A214524, A214530. Sequence in context: A044011 A338039 A085504 * A271502 A235641 A087636 Adjacent sequences:  A214528 A214529 A214530 * A214532 A214533 A214534 KEYWORD nonn,base,easy AUTHOR Jonathan Vos Post, Jul 20 2012 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 12 14:32 EDT 2021. Contains 344957 sequences. (Running on oeis4.)