A130232 a(1) = 0; a(n) = a(n-1) + (number of times the digit 0 has appeared in the sequence so far).

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 23, 26, 29, 32, 35, 38, 41, 44, 47, 50, 54, 58, 62, 66, 70, 75, 80, 86, 92, 98, 104, 111, 118, 125, 132, 139, 146, 153, 160, 168, 176, 184, 192, 200, 210, 221, 232, 243, 254, 265, 276, 287, 298, 309, 321, 333, 345, 357, 369

Offset

1,3

Links

Table of n, a(n) for n=1..65.

Maple

A130232 := proc(n)
    option remember;
    if n = 1 then
        0;
    else
        a := procname(n-1) ;
        for j from 1 to n-1 do
            for d in convert(procname(j), base, 10) do
                if d = 0 then
                    a := a+1 ;
                end if;
            end do:
        end do:
        a+1 ;
    end if;
end proc:
seq(A130232(n), n=1..80) ; # R. J. Mathar, Aug 06 2016

Mathematica

ss=s={0}; Do[a=ss[[-1]]+Count[s, 0]; s=Join[s, IntegerDigits[a]]; AppendTo[ss, a], {n, 64}]; ss (* James C. McMahon, Feb 08 2025 *)

Prog

(Python)
A130232_list, c = [0], 1
for _ in range(100):
    A130232_list.append(A130232_list[-1]+c)
    c += str(A130232_list[-1]).count('0') # Chai Wah Wu, Jun 06 2021

Crossrefs

Sequence in context: A033062 A060472 A130514 * A103969 A271168 A292514

Adjacent sequences: A130229 A130230 A130231 * A130233 A130234 A130235

Keyword

base,easy,nonn,changed

Author

Eric Angelini, Aug 05 2007

Extensions

Corrected by R. J. Mathar, Aug 06 2016

Status

approved