A043493 -id:A043493 - cp's OEIS frontend

A043525 Numbers having one 9 in base 10.

9, 19, 29, 39, 49, 59, 69, 79, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 109, 119, 129, 139, 149, 159, 169, 179, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 209, 219, 229, 239, 249, 259, 269, 279, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 309, 319

Offset: 1

Clark Kimberling

Enrique Pérez Herrero, Table of n, a(n) for n = 1..2000
Index entries for 10-automatic sequences.

Cf. A043489, A043493, A043497, A043501, A043505, A043509, A043513, A043517, A043521.
Cf. A011539, A140502.
Subsequence of A011539.

Select[Range[300],DigitCount[#,10,9]==1&] (* Harvey P. Dale, Jan 19 2013 *)

def ok(n): return str(n).count('9') == 1
print(list(filter(ok, range(320)))) # Michael S. Branicky, Sep 19 2021

Sum_{n>=1} 1/a(n) = A140502. - Amiram Eldar, Nov 14 2020

A259528 n-th number with exactly n n's in base 10.

Original entry on oeis.org

1, 122, 2333, 34444, 455555, 5666666, 67777777, 788888888, 8999999999, 101010101010101010010, 11111111110111111111111, 1212121121212121212121212, 131313013131313131313131313, 14141241414141414141414141414

Offset: 1

Jonathan Vos Post, Jun 29 2015

Main diagonal M[n,n,n] of M[i,j,k] = k-th natural number such that number of i's in base 10 is j, for i,j,k = 1,2,3,4,5,....
M[1,1,n] = A043493 Numbers that contain a single 1.
M[2,2,n] = A043498 Numbers n such that number of 2's in base 10 is 2.
M[3,3,n] = A043503 Numbers n such that number of 3's in base 10 is 3.
M[4,4,n] = A043508 Numbers n such that number of 4's in base 10 is 4.

			First element is 1, the 1st natural number with exactly one 1 in base 10.
Second element is 122, the 2nd natural number with exactly two 2's in base 10.
Third element is 2333, the 3rd natural number with exactly three 3's in base 10.

Cf. A043493, A043498, A043503, A043508.

a(n)=my(v=List(),k=10^#Str(n),d=List(digits((k^n-1)/(k-1)*n)),t); for(i=1,#d+1, t=d; listinsert(t,0,i); t=Vec(t); for(j=0,9, t[i]=j; listput(v,fromdigits(t)))); Set(v)[n] \\ Charles R Greathouse IV, Jun 29 2015

a(5)-a(14) from Charles R Greathouse IV, Jun 29 2015

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A043525 Numbers having one 9 in base 10.

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A259528 n-th number with exactly n n's in base 10.

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