login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A220570 Numbers that are not Brazilian numbers. 9
1, 2, 3, 4, 5, 6, 9, 11, 17, 19, 23, 25, 29, 37, 41, 47, 49, 53, 59, 61, 67, 71, 79, 83, 89, 97, 101, 103, 107, 109, 113, 131, 137, 139, 149, 151, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 223, 227, 229, 233, 239, 251, 257, 263, 269, 271, 277, 281 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

"Nombres brésiliens" in French. There is an infinity of numbers that are not Brazilian numbers. See links: Quadrature (Corollaire 2).

REFERENCES

Pierre Bornsztein, "Hypermath", Vuibert, Exercise a35, page 7.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Bernard Schott, Les nombres brésiliens, Quadrature, no. 76, avril-juin 2010, pages 30-38; included here with permission from the editors of Quadrature.

EXAMPLE

25 is a member because it's not possible to write 25=(mm...mm)_b where b is a natural number with 1 < b < 24 and 1 <= m < b.

PROG

(PARI) for(n=1, 300, c=0; for(b=2, n-2, d=digits(n, b); if(vecmin(d)==vecmax(d), c=n; break); c++); if(c==max(n-3, 0), print1(n, ", "))) \\ Derek Orr, Apr 30 2015

CROSSREFS

Cf. A125134, A190300, A220136.

Sequence in context: A102571 A251241 A064278 * A125155 A091179 A036027

Adjacent sequences:  A220567 A220568 A220569 * A220571 A220572 A220573

KEYWORD

nonn,easy

AUTHOR

Bernard Schott, Dec 16 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified August 22 07:02 EDT 2017. Contains 290943 sequences.