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.

A325203 a(n) is 10^n represented in bijective base-9 numeration.

Original entry on oeis.org

1, 11, 121, 1331, 14641, 162151, 1783661, 19731371, 228145181, 2519596991, 27726678111, 315994569221, 3477151372431, 38358665196741, 432956427275251, 4763631711137761, 53499948822526471, 588621548147792281, 6585837139636825191, 73555318547116177211
Offset: 0

Views

Author

Alois P. Heinz, Sep 05 2019

Keywords

Comments

Differs from A055479 first at n = 7: a(7) = 19731371 < 20731371 = A055479(7).
Also: the (10^n)-th zeroless number. - M. F. Hasler, Jan 13 2020

Examples

			a(1) = 11_bij9   =                 1*9^1 + 1*9^0 =           9+1 =   10.
a(2) = 121_bij9  =         1*9^2 + 2*9^1 + 1*9^0 =       81+18+1 =  100.
a(3) = 1331_bij9 = 1*9^3 + 3*9^2 + 3*9^1 + 1*9^0 =  729+243+27+1 = 1000.
a(7) = 19731371_bij9 = 9*(9*(9*(9*(9*(9*(9*1+9)+7)+3)+1)+3)+7)+1 = 10^7.
		

Crossrefs

Cf. A011557, A052382 (zeroless numbers), A055479, A309908.

Programs

  • Maple
    b:= proc(n) local d, l, m; m:= n; l:= "";
          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:
    a:= n-> b(10^n):
    seq(a(n), n=0..23);
  • PARI
    A325203(n)=A052382(10^n) \\ M. F. Hasler, Jan 13 2020

Formula

a(n) = A052382(10^n) = A052382(A011557(n)).