A139819 Complement of repdigit numbers A010785.

10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 89

Offset

1,1

Comments

Identical to (base 10) non-palindromic numbers A029742 up to a(83) = 101 which is a term of this sequence but not in A029742. - M. F. Hasler, Sep 08 2015

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Repdigit.

Wikipedia, Repdigit

Chai Wah Wu, Algorithms for complementary sequences, arXiv:2409.05844 [math.NT], 2024.

Formula

A202022(a(n)) = 0. - Reinhard Zumkeller, Dec 09 2011

Maple

isA139819 := proc(n)
    convert(n, base, 10) ;
    convert(%, set) ;
    simplify(nops(%) >1 ) ;
end proc: # R. J. Mathar, Jan 17 2017

Prog

(Haskell) a139819 n = a139819_list !! (n-1)
a139819_list = filter ((== 0) . a202022) [0..] -- Reinhard Zumkeller, Dec 09 2011
(PARI) is_A139819(n)=#Set(digits(n))>1 \\ M. F. Hasler, Sep 08 2015
(Python)
def A139819(n):
    m, k = n, n+9*((l:=len(str(n)))-1)+9*n//(10**l-1)
    while m != k:
        m, k = k, n+9*((l:=len(str(k)))-1)+9*k//(10**l-1)
    return m # Chai Wah Wu, Sep 04 2024

Crossrefs

Cf. A066484 (subsequence).

Cf. A029742 (non-palindromic in base 10), A016038 (in any base), A050813 (in bases 2..10).

Sequence in context: A109394 A285687 A139704 * A288040 A031955 A029742

Adjacent sequences: A139816 A139817 A139818 * A139820 A139821 A139822

Keyword

nonn,base

Author

N. J. A. Sloane, Jun 02 2008

Status

approved