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A152054 Bouncy numbers (numbers whose digits are in neither increasing nor decreasing order). 6
101, 102, 103, 104, 105, 106, 107, 108, 109, 120, 121, 130, 131, 132, 140, 141, 142, 143, 150, 151, 152, 153, 154, 160, 161, 162, 163, 164, 165, 170, 171, 172, 173, 174, 175, 176, 180, 181, 182, 183, 184, 185, 186, 187, 190, 191, 192, 193, 194, 195, 196 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of union of A009994 and A009996. - Ray Chandler, Oct 25 2011

Number of n-digit bouncy numbers is 9*10^(n-1) - (n+18)*binomial(n+8, 8)/9 + 10. - Altug Alkan, Oct 02 2018

LINKS

David F. Marrs, Table of n, a(n) for n = 1..10000

Project Euler, Non-bouncy numbers Problem 113

MATHEMATICA

Select[Range[0, 200], !LessEqual@@IntegerDigits[#] && !GreaterEqual@@IntegerDigits[#]&] (* Ray Chandler, Oct 25 2011 *)

bnQ[n_]:=Module[{didn=Differences[IntegerDigits[n]]}, Count[didn, _?(#>0&)]>0 && Count[didn, _?(#<0&)]>0]; Select[Range[100, 200], bnQ] (* Harvey P. Dale, Jun 13 2020 *)

PROG

(Python)

a = 1

b = 100

while a != 51:

    if str(b) != ''.join(sorted(str(b))) and str(b) != ''.join(sorted(str(b)))[::-1]:

        print(b)

        a += 1

    b += 1

# David F. Marrs, Sep 25 2018

CROSSREFS

Cf. A152464. - Jon E. Schoenfield, Dec 06 2008

Cf. A009994, A009996, A204692.

Sequence in context: A284180 A138719 A043639 * A296883 A183086 A134808

Adjacent sequences:  A152051 A152052 A152053 * A152055 A152056 A152057

KEYWORD

nonn,base,easy

AUTHOR

Jerome Abela (Jerome.Abela(AT)gmail.com), Nov 22 2008

EXTENSIONS

More terms from Jon E. Schoenfield, Dec 06 2008

STATUS

approved

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Last modified June 14 14:21 EDT 2021. Contains 345025 sequences. (Running on oeis4.)