cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-8 of 8 results.

A052382 Numbers without 0 in the decimal expansion, colloquial 'zeroless numbers'.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 96, 97, 98, 99, 111, 112, 113
Offset: 1

Views

Author

Henry Bottomley, Mar 13 2000

Keywords

Comments

The entries 1 to 79 match the corresponding subsequence of A043095, but then 81, 91-98, 100, 102, etc. are only in one of the two sequences. - R. J. Mathar, Oct 13 2008
Complement of A011540; A168046(a(n)) = 1; A054054(a(n)) > 0; A007602, A038186, A038618, A052041, A052043, and A052045 are subsequences. - Reinhard Zumkeller, Apr 25 2012, Apr 07 2011, Dec 01 2009
a(n) = n written in base 9 where zeros are not allowed but nines are. The nine distinct digits used are 1, 2, 3, ..., 9 instead of 0, 1, 2, ..., 8. To obtain this sequence from the "canonical" base 9 sequence with zeros allowed, just replace any 0 with a 9 and then subtract one from the group of digits situated on the left. For example, 9^3 = 729 (10) (in base 10) = 1000 (9) (in base 9) = 889 (9-{0}) (in base 9 without zeros) because 100 (9) = [9-1]9 = 89 (9-{0}) and thus 1000 (9) = [89-1]9 = 889 (9-{0}). - Robin Garcia, Jan 15 2014
From Hieronymus Fischer, May 28 2014: (Start)
Inversion: Given a term m, the index n such that a(n) = m can be calculated by A052382_inverse(m) = m - sum_{1<=j<=k} floor(m/10^j)*9^(j-1), where k := floor(log_10(m)) [see Prog section for an implementation in Smalltalk].
Example 1: A052382_inverse(137) = 137 - (floor(137/10) + floor(137/100)*9) = 137 - (13*1 + 1*9) = 137 - 22 = 115.
Example 2: A052382_inverse(4321) = 4321 - (floor(4321/10) + floor(4321/100)*9 + floor(4321/1000)*81) = 4321 - (432*1 + 43*9 + 4*81) = 4321 - (432 + 387 + 324) = 3178. (End)
The sum of the reciprocals of these numbers from a(1)=1 to infinity, called the Kempner series, is convergent towards a limit: 23.103447... whose decimal expansion is in A082839. - Bernard Schott, Feb 23 2019
Integer n > 0 is encoded using bijective base-9 numeration, see Wikipedia link below. - Alois P. Heinz, Feb 16 2020

Examples

			For k >= 0, a(10^k) = (1, 11, 121, 1331, 14641, 162151, 1783661, 19731371, ...) = A325203(k). - _Hieronymus Fischer_, May 30 2012 and Jun 06 2012; edited by _M. F. Hasler_, Jan 13 2020
		

References

  • Paul Halmos, "Problems for Mathematicians, Young and Old", Dolciani Mathematical Expositions, 1991, p. 258.

Crossrefs

Cf. A004719, A052040, different from A067251.
Column k=9 of A214676.
Cf. A011540 (complement), A043489, A054054, A168046.
Cf. A052383 (without 1), A052404 (without 2), A052405 (without 3), A052406 (without 4), A052413 (without 5), A052414 (without 6), A052419 (without 7), A052421 (without 8), A007095 (without 9).
Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A248910 (base 6), A255805 (base 8), A255808 (base 9).
Cf. A082839 (sum of reciprocals).
Cf. A038618 (subset of primes)

Programs

  • Haskell
    a052382 n = a052382_list !! (n-1)
    a052382_list = iterate f 1 where
    f x = 1 + if r < 9 then x else 10 * f x' where (x', r) = divMod x 10
    -- Reinhard Zumkeller, Mar 08 2015, Apr 07 2011
    
  • Magma
    [ n: n in [1..114] | not 0 in Intseq(n) ]; // Bruno Berselli, May 28 2011
    
  • Maple
    a:= proc(n) local d, l, m; m:= n; l:= NULL;
          while m>0 do d:= irem(m, 9, 'm');
            if d=0 then d:=9; m:= m-1 fi;
            l:= d, l
          od; parse(cat(l))
        end:
    seq(a(n), n=1..100);  # Alois P. Heinz, Jan 11 2015
    is_zeroless := n -> not is(0 in convert(n, base, 10)):
    select(is_zeroless, [seq(1..113)]);  # Peter Luschny, Jun 20 2025
  • Mathematica
    A052382 = Select[Range[100], DigitCount[#, 10, 0] == 0 &] (* Alonso del Arte, Mar 10 2011 *)
  • PARI
    select( {is_A052382(n)=n&&vecmin(digits(n))}, [0..111]) \\ actually: is_A052382 = (bool) A054054. - M. F. Hasler, Jan 23 2013, edited Jan 13 2020
    
  • PARI
    a(n) = for (w=0, oo, if (n >= 9^w, n -= 9^w, return ((10^w-1)/9 + fromdigits(digits(n, 9))))) \\ Rémy Sigrist, Jul 26 2017
    
  • PARI
    apply( {A052382(n,L=logint(n,9))=fromdigits(digits(n-9^L>>3,9))+10^L\9}, [1..100])
    next_A052382(n, d=digits(n+=1))={for(i=1, #d, d[i]|| return(n-n%(d=10^(#d-i+1))+d\9)); n} \\ least a(k) > n. Used in A038618.
    ( {A052382_vec(n,M=1)=M--;vector(n, i, M=next_A052382(M))} )(99) \\ n terms >= M
    \\ See OEIS Wiki page (cf. LINKS) for more programs. - M. F. Hasler, Jan 11 2020
    
  • Python
    A052382 = [n for n in range(1,10**5) if not str(n).count('0')]
    # Chai Wah Wu, Aug 26 2014
    
  • Python
    from sympy import integer_log
    def A052382(n):
        m = integer_log(k:=(n<<3)+1,9)[0]
        return sum((1+(k-9**m)//(9**j<<3)%9)*10**j for j in range(m)) # Chai Wah Wu, Jun 27 2025
  • Smalltalk
    A052382
    "Answers the n-th term of A052382, where n is the receiver."
    ^self zerofree: 10
    A052382_inverse
    "Answers that index n which satisfy A052382(n) = m, where m is the receiver.”
    ^self zerofree_inverse: 10
    zerofree: base
    "Answers the n-th zerofree number in base base, where n is the receiver. Valid for base > 2.
    Usage: n zerofree: b [b = 10 for this sequence]
    Answer: a(n)"
    | n m s c bi ci d |
    n := self.
    c := base - 1.
    m := (base - 2) * n + 1 integerFloorLog: c.
    d := n - (((c raisedToInteger: m) - 1)//(base - 2)).
    bi := 1.
    ci := 1.
    s := 0.
    1 to: m
    do:
    [:i |
    s := (d // ci \\ c + 1) * bi + s.
    bi := base * bi.
    ci := c * ci].
    ^s
    zerofree_inverse: base
    "Answers the index n such that the n-th zerofree number in base base is = m, where m is the receiver. Valid for base > 2.
    Usage: m zerofree_inverse: b [b = 10 for this sequence]
    Answer: n"
    | m p q s |
    m := self.
    s := 0.
    p := base.
    q := 1.
    [p < m] whileTrue:
    [s := m // p * q + s.
    p := base * p.
    q := (base - 1) * q].
    ^m - s
    "by Hieronymus Fischer, May 28 2014"
    
  • sh
    seq 0 1000 | grep -v 0; # Joerg Arndt, May 29 2011
    

Formula

a(n+1) = f(a(n)) with f(x) = 1 + if x mod 10 < 9 then x else 10*f([x/10]). - Reinhard Zumkeller, Nov 15 2009
From Hieronymus Fischer, Apr 30, May 30, Jun 08 2012, Feb 17 2019: (Start)
a(n) = Sum_{j=0..m-1} (1 + b(j) mod 9)*10^j, where m = floor(log_9(8*n + 1)), b(j) = floor((8*n + 1 - 9^m)/(8*9^j)).
Also: a(n) = Sum_{j=0..m-1} (1 + A010878(b(j)))*10^j.
a(9*n + k) = 10*a(n) + k, k=1..9.
Special values:
a(k*(9^n - 1)/8) = k*(10^n - 1)/9, k=1..9.
a((17*9^n - 9)/8) = 2*10^n - 1.
a((9^n - 1)/8 - 1) = 10^(n-1) - 1, n > 1.
Inequalities:
a(n) <= (1/9)*((8*n+1)^(1/log_10(9)) - 1), equality holds for n=(9^k-1)/8, k>0.
a(n) > (1/10)*((8*n+1)^(1/log_10(9)) - 1), n > 0.
Lower and upper limits:
lim inf a(n)/10^log_9(8*n) = 1/10, for n -> infinity.
lim inf a(n)/n^(1/log_10(9)) = 8^(1/log_10(9))/10, for n -> infinity.
lim sup a(n)/10^log_9(8*n) = 1/9, for n -> infinity.
lim sup a(n)/n^(1/log_10(9)) = 8^(1/log_10(9))/9, for n -> infinity.
G.f.: g(x) = (x^(1/8)*(1-x))^(-1) Sum_{j>=0} 10^j*z(j)^(9/8)*(1 - 10z(j)^9 + 9z(j)^10)/((1-z(j))(1-z(j)^9)), where z(j) = x^9^j.
Also: g(x) = (1/(1-x)) Sum_{j>=0} (1 - 10(x^9^j)^9 + 9(x^9^j)^10)*x^9^j*f_j(x)/(1-x^9^j), where f_j(x) = 10^j*x^((9^j-1)/8)/(1-(x^9^j)^9). Here, the f_j obey the recurrence f_0(x) = 1/(1-x^9), f_(j+1)(x) = 10x*f_j(x^9).
Also: g(x) = (1/(1-x))*((Sum{k=0..8} h_(9,k)(x)) - 9*h_(9,9)(x)), where h_(9,k)(x) = Sum_{j>=0} 10^j*x^((9^(j+1)-1)/8)*x^(k*9^j)/(1-x^9^(j+1)).
Generic formulas for analogous sequences with numbers expressed in base p and only using the digits 1, 2, 3, ... d, where 1 < d < p:
a(n) = Sum_{j=0..m-1} (1 + b(j) mod d)*p^j, where m = floor(log_d((d-1)*n+1)), b(j) = floor(((d-1)*n+1-d^m)/((d-1)*d^j)).
Special values:
a(k*(d^n-1)/(d-1)) = k*(10^n-1)/9, k=1..d.
a(d*((2d-1)*d^(n-1)-1)/(d-1)) = ((d+9)*10^n-d)/9 = 10^n + d*(10^n-1)/9.
a((d^n-1)/(d-1)-1) = d*(10^(n-1)-1)/9, n > 1.
Inequalities:
a(n) <= (10^log_d((d-1)*n+1)-1)/9, equality holds for n = (d^k-1)/(d-1), k > 0.
a(n) > (d/10)*(10^log_d((d-1)*n+1)-1)/9, n > 0.
Lower and upper limits:
lim inf a(n)/10^log_d((d-1)*n) = d/90, for n -> infinity.
lim sup a(n)/10^log_d((d-1)*n) = 1/9, for n -> infinity.
G.f.: g(x) = (1/(1-x)) Sum_{j>=0} (1 - (d+1)(x^d^j)^d + d(x^d^j)^(d+1))*x^d^j*f_j(x)/(1-x^d^j), where f_j(x) = p^j*x^((d^j-1)/(d-1))/(1-(x^d^j)^d). Here, the f_j obey the recursion f_0(x) = 1/(1-x^d), f_(j+1)(x) = px*f_j(x^d).
(End)
A052382 = { n | A054054(n) > 0 }. - M. F. Hasler, Jan 23 2013
From Hieronymus Fischer, Feb 20 2019: (Start)
Sum_{n>=1} (-1)^(n+1)/a(n) = 0.696899720...
Sum_{n>=1} 1/a(n)^2 = 1.6269683705819...
Sum_{n>=1} 1/a(n) = 23.1034479... = A082839. This so-called Kempner series converges very slowly. For the calculation of the sum, it is helpful to use the following fraction of partial sums, which converges rapidly:
lim_{n->infinity} (Sum_{k=p(n)..p(n+1)-1} 1/a(k)) / (Sum_{k=p(n-1)..p(n)-1} 1/a(k)) = 9/10, where p(n) = (9^n-1)/8, n > 1.
(End)

Extensions

Typos in formula section corrected by Hieronymus Fischer, May 30 2012
Name clarified by Peter Luschny, Jun 20 2025

A032924 Numbers whose ternary expansion contains no 0.

Original entry on oeis.org

1, 2, 4, 5, 7, 8, 13, 14, 16, 17, 22, 23, 25, 26, 40, 41, 43, 44, 49, 50, 52, 53, 67, 68, 70, 71, 76, 77, 79, 80, 121, 122, 124, 125, 130, 131, 133, 134, 148, 149, 151, 152, 157, 158, 160, 161, 202, 203, 205, 206, 211, 212, 214, 215, 229, 230, 232, 233, 238, 239
Offset: 1

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Author

Keywords

Comments

Complement of A081605. - Reinhard Zumkeller, Mar 23 2003
Subsequence of A154314. - Reinhard Zumkeller, Jan 07 2009
The first 28 terms are the range of A059852 (Morse codes for letters, when written in base 3) union {44, 50} (which correspond to Morse codes of Ü and Ä). Subsequent terms represent the Morse code of other symbols in the same coding. - M. F. Hasler, Jun 22 2020

Crossrefs

Zeroless numbers in some other bases <= 10: A000042 (base 2), A023705 (base 4), A248910 (base 6), A255805 (base 8), A255808 (base 9), A052382 (base 10).

Programs

  • Haskell
    a032924 n = a032924_list !! (n-1)
    a032924_list = iterate f 1 where
       f x = 1 + if r < 2 then x else 3 * f x'  where (x', r) = divMod x 3
    -- Reinhard Zumkeller, Mar 07 2015, May 04 2012
    
  • Maple
    f:= proc(n) local L,i,m;
       L:= convert(n,base,2);
       m:= nops(L);
       add((1+L[i])*3^(i-1),i=1..m-1);
    end proc:
    map(f, [$2..101]); # Robert Israel, Aug 04 2015
  • Mathematica
    Select[Range@ 240, Last@ DigitCount[#, 3] == 0 &] (* Michael De Vlieger, Aug 05 2015 *)
    Flatten[Table[FromDigits[#,3]&/@Tuples[{1,2},n],{n,5}]] (* Harvey P. Dale, May 28 2016 *)
  • PARI
    apply( {A032924(n)=if(n<3,n,3*self()((n-1)\2)+2-n%2)}, [1..99]) \\ M. F. Hasler, Jun 22 2020
    
  • PARI
    a(n) = fromdigits(apply(d->d+1,binary(n+1)[^1]), 3); \\ Kevin Ryde, Jun 23 2020
    
  • Python
    def a(n): return sum(3**i*(int(b)+1) for i, b in enumerate(bin(n+1)[:2:-1]))
    print([a(n) for n in range(1, 61)]) # Michael S. Branicky, Aug 15 2022
    
  • Python
    def is_A032924(n):
        while n > 2:
           n,r = divmod(n,3)
           if r==0: return False
        return n > 0
    print([n for n in range(250) if is_A032924(n)]) # M. F. Hasler, Feb 15 2023
    
  • Python
    def A032924(n): return int(bin(m:=n+1)[3:],3) + (3**(m.bit_length()-1)-1>>1) # Chai Wah Wu, Oct 13 2023

Formula

a(n) = A107680(n) + A107681(n). - Reinhard Zumkeller, May 20 2005
A081604(A107681(n)) <= A081604(A107680(n)) = A081604(a(n)) = A000523(n+1). - Reinhard Zumkeller, May 20 2005
A077267(a(n)) = 0. - Reinhard Zumkeller, Mar 02 2008
a(1)=1, a(n+1) = f(a(n)+1,a(n)+1) where f(x,y) = if x<3 and x<>0 then y, else if x mod 3 = 0 then f(y+1,y+1), else f(floor(x/3),y). - Reinhard Zumkeller, Mar 02 2008
a(2*n) = a(2*n-1)+1, n>0. - Zak Seidov, Jul 27 2009
A212193(a(n)) = 0. - Reinhard Zumkeller, May 04 2012
a(2*n+1) = 3*a(n)+1. - Robert Israel, Aug 05 2015
G.f.: x/(1-x)^2 + Sum_{m >= 1} 3^(m-1)*x^(2^(m+1)-1)/((1-x^(2^m))*(1-x)). - Robert Israel, Aug 04 2015
A065361(a(n)) = n. - Rémy Sigrist, Feb 06 2023
Sum_{n>=1} 1/a(n) = 3.4977362637842652509313189236131190039368413460747606236619907531632476445332666030262441154353753276457... (calculated using Baillie and Schmelzer's kempnerSums.nb, see Links). - Amiram Eldar, Apr 14 2025

A100969 Integers that are Rhonda numbers to base 6.

Original entry on oeis.org

855, 1029, 3813, 5577, 7040, 7304, 15104, 19136, 35350, 36992, 41031, 42009, 60368, 65536, 67821, 76880, 84525, 90601, 122831, 131175, 154570, 162565, 184009, 184585, 196504, 217021, 219830, 222200, 252161, 256041, 268677, 353115, 355737, 357568, 367517, 371229, 388367
Offset: 1

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Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 24 2004

Keywords

Comments

See sequence A099542 for definition of Rhonda numbers and links.

Examples

			The product of the base 6 digits of 507500 is 1*4*5*1*3*3*1*2=360 and the sum of the prime factors of 507500 is 2*2+4*5+7+29=60 and 360=6*60.
		

Crossrefs

Cf. Rhonda numbers to other bases: A100968 (base 4), A100970 (base 8), A100973 (base 9), A099542 (base 10), A100971 (base 12), A100972 (base 14), A100974 (base 15), A100975 (base 16), A255735 (base 18), A255732 (base 20), A255736 (base 30), A255731 (base 60), see also A255872.
Cf. A001414, A027746, A007092, subsequence of A248910.
Column k=2 of A291925.

Programs

  • Haskell
    a100969 n = a100969_list !! (n-1)
    a100969_list = filter (rhonda 6) a248910_list
    -- Function rhonda as in A099542.
    -- Reinhard Zumkeller, Mar 08 2015
  • Mathematica
    A100969Q[k_] := Times @@ IntegerDigits[k, 6] == 6*Total[Times @@@ FactorInteger[k]];
    Select[Range[400000], A100969Q] (* Paolo Xausa, Jul 01 2025 *)

A023705 Numbers with no 0's in base-4 expansion.

Original entry on oeis.org

1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 21, 22, 23, 25, 26, 27, 29, 30, 31, 37, 38, 39, 41, 42, 43, 45, 46, 47, 53, 54, 55, 57, 58, 59, 61, 62, 63, 85, 86, 87, 89, 90, 91, 93, 94, 95, 101, 102, 103, 105, 106, 107, 109, 110, 111, 117, 118, 119, 121, 122, 123
Offset: 1

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Author

Keywords

Comments

A032925 is the intersection of this sequence and A023717; cf. A179888. - Reinhard Zumkeller, Jul 31 2010

Crossrefs

Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A248910 (base 6), A255805 (base 8), A255808 (base 9), A052382 (base 10).
Cf. A100968 (subsequence).

Programs

  • C
    #include 
    uint32_t a_next(uint32_t a_n) { return (a_n + 1) | ((a_n & (a_n + 0xaaaaaaab)) >> 1); } /* Falk Hüffner, Jan 22 2022 */
    
  • Haskell
    a023705 n = a023705_list !! (n-1)
    a023705_list = iterate f 1 where
       f x = 1 + if r < 3 then x else 4 * f x'
             where (x', r) = divMod x 4
    -- Reinhard Zumkeller, Mar 06 2015, Oct 19 2011
    
  • Magma
    [n: n in [1..130] | not 0 in Intseq(n,4)]; // Vincenzo Librandi, Oct 04 2018
    
  • Maple
    R:= [1,2,3]: A:= 1,2,3:
    for i from 1 to 4 do
      R:= map(t -> (4*t+1,4*t+2,4*t+3), R);
      A:= A, op(R);
    od:
    A; # Robert Israel, Oct 04 2018
  • Mathematica
    Select[ Range[ 120 ], (Count[ IntegerDigits[ #, 4 ], 0 ]==0)& ]
    Select[Range[200],DigitCount[#,4,0]==0&] (* Harvey P. Dale, Dec 23 2015 *)
  • PARI
    isok(n) = vecmin(digits(n, 4)); \\ Michel Marcus, Jul 04 2015
    
  • Python
    from sympy import integer_log
    def A023705(n):
        m = integer_log(k:=(n<<1)+1,3)[0]
        return sum(1+(k-3**m)//(3**j<<1)%3<<(j<<1) for j in range(m)) # Chai Wah Wu, Jun 27 2025

Formula

G.f. g(x) satisfies g(x) = (x+2*x^2+3*x^3)/(1-x^3) + 4*(x+x^2+x^3)*g(x^3). - Robert Israel, Oct 04 2018

A255805 Numbers with no zeros in base-8 representation.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 62, 63, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84
Offset: 1

Views

Author

Reinhard Zumkeller, Mar 08 2015

Keywords

Comments

Different from A047592, A207481.

Crossrefs

Cf. A007094, A100970 (subsequence).
Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A248910 (base 6), A255808 (base 9), A052382 (base 10).

Programs

  • Haskell
    a255805 n = a255805_list !! (n-1)
    a255805_list = iterate f 1 where
       f x = 1 + if r < 7 then x else 8 * f x'  where (x', r) = divMod x 8
    
  • Mathematica
    Select[Range[100],DigitCount[#,8,0]==0&] (* Harvey P. Dale, Jun 08 2015 *)
  • PARI
    isok(m) = vecmin(digits(m,8)) > 0; \\ Michel Marcus, Jan 23 2022
    
  • Python
    def ok(n): return '0' not in oct(n)[2:]
    print([k for k in range(85) if ok(k)]) # Michael S. Branicky, Jan 23 2022
    
  • Python
    from sympy import integer_log
    def A255805(n):
        m = integer_log(k:=6*n+1,7)[0]
        return sum(1+(k-7**m)//(6*7**j)%7<<3*j for j in range(m)) # Chai Wah Wu, Jun 28 2025

A255808 Numbers with no zeros in base-9 representation.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 46, 47, 48, 49, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75
Offset: 1

Views

Author

Reinhard Zumkeller, Mar 08 2015

Keywords

Comments

a(n) = A168183(n) for n <= 72.

Crossrefs

Cf. A007095, A100973 (subsequence).
Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A248910 (base 6), A255805 (base 8), A052382 (base 10).

Programs

  • Haskell
    a255808 n = a255808_list !! (n-1)
    a255808_list = iterate f 1 where
       f x = 1 + if r < 8 then x else 9 * f x'  where (x', r) = divMod x 9
    
  • Mathematica
    Select[Range[100],DigitCount[#,9,0]==0&] (* or *) With[{upto=100}, Complement[ Range[upto],9*Range[Floor[upto/9]]]] (* Harvey P. Dale, May 29 2019 *)
  • PARI
    isok(n) = vecmin(digits(n, 9)) != 0; \\ Michel Marcus, Jun 29 2019
    
  • Python
    def A255808(n):
        m = ((k:=7*n+1).bit_length()-1)//3
        return sum((1+((k-(1<<3*m))//(7<<3*j)&7))*9**j for j in range(m)) # Chai Wah Wu, Jun 28 2025

A382416 Numbers with at least one zero in their base-6 representation.

Original entry on oeis.org

0, 6, 12, 18, 24, 30, 36, 37, 38, 39, 40, 41, 42, 48, 54, 60, 66, 72, 73, 74, 75, 76, 77, 78, 84, 90, 96, 102, 108, 109, 110, 111, 112, 113, 114, 120, 126, 132, 138, 144, 145, 146, 147, 148, 149, 150, 156, 162, 168, 174, 180, 181, 182, 183, 184, 185, 186, 192, 198
Offset: 1

Views

Author

Paolo Xausa, Mar 25 2025

Keywords

Crossrefs

Cf. analogous sequences in other bases: A062289 (base 2), A081605 (base 3), A196032 (base 4), A382415 (base 5), A382413 (base 7), A382417 (base 8), A382418 (base 9), A011540 (base 10).
Cf. A007092, A043369, A248910 (complement).

Programs

  • Mathematica
    Select[Range[0, 200], DigitCount[#, 6, 0] > 0 &]

A382412 Numbers with no zeros in their base-7 representation.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89, 90
Offset: 1

Views

Author

Paolo Xausa, Mar 24 2025

Keywords

Crossrefs

Cf. zeroless numbers in other bases: A126646 (base 2), A032924 (base 3), A023705 (base 4), A023721 (base 5), A248910 (base 6), A255805 (base 8), A255808 (base 9), A052382 (base 10).
Cf. A007093, A043393, A249102, A382413 (complement).

Programs

  • Mathematica
    Select[Range[100], DigitCount[#, 7, 0] == 0 &]
Showing 1-8 of 8 results.